• How to configure OpenDKIM on Linux with Postfix and setup bind zonefile


    This guide assumes you have a working Postfix server and want it to sign with DKIM. There are a few things we have to understand to make all of this work though, which require you to be familiar with DNS as well. 1.) Install OpenDKIM apt install opendkim systemctl enable opendkim 2.) Edit /etc/opendkim.conf Syslog yes SyslogSuccess yes Mode&nbs........
  • Debian Ubuntu 10/11/12 Linux how to get tftpd-hpa server setup tutorial


    apt install tftpd-hpa #change TFTP_ADDRESS to by setting address to 192.168.1.1:69 or the IP you need, otherwise it will listen on all IPs and interfaces which could be a security risk. # edit /etc/default/tftpd-hpa TFTP_USERNAME="tftp" TFTP_DIRECTORY="/srv/tftp" TFTP_ADDRESS="192.168.1.1:69" TFTP_OPTIONS="--secure"........
  • Apache Error Won't start SSL Cert Issue Solution Unable to configure verify locations for client authentication SSL Library Error: 151441510 error:0906D066:PEM routines:PEM_read_bio:bad end line SSL Library Error: 185090057 error:0B084009:x509 certif


    [Wed Nov 01 18:47:08 2023] [error] Unable to configure verify locations for client authentication [Wed Nov 01 18:47:08 2023] [error] SSL Library Error: 151441510 error:0906D066:PEM routines:PEM_read_bio:bad end line [Wed Nov 01 18:47:08 2023] [error] SSL Library Error: 185090057 error:0B084009:x509 certificate routines:X509_load_cert_crl_file:PEM lib It actually gives us a good clue that at last one component of our cert is invalid/improperl........
  • How to kill a docker swarm


    Assign way more replicas than you have of memory on all nodes and watch the Swarm crash which can easily reproduce in a small VMfor testing. root@Deb11Docker01:~# docker ps CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAM........
  • [error] (28)No space left on device: Cannot create SSLMutex Apache Solution Linux CentOS Ubuntu Debian Mint


    Have you got this error from Apache? [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [error] (28)No space left on device: Cannot create SSLMutex At first glance it appears that you may be out of disk space but the issue is ipc or interprocess communication. This will clear out the ipcs processes so things can work, this often happens during high traffic and may be a sign of DDOS. The command below will fix it, it will list al........
  • Save money on bandwidth by disabling reflective rpc queries in Linux CentOS RHEL Ubuntu Debian


    Even today we see a lot of servers that have different services and ports open for rpc and this creates not only potential inward vulnerabilities but perhaps more common, the abuse of your network resources in reflective rpc queries. To stop this problem, you should disable and remove all services relating to rpc or at least block all relevant ports for the service. Surprisingly, there are still some providers and OS installs in Linux that install these services and leave them........
  • Linux custom kernel is huge solution


    You may have been expecting a normal sized kernel but if you don't disable these .config options you may have a kernel that is several gigabytes. CONFIG_SLUB_DEBUG=no CONFIG_DEBUG_INFO=no CONFIG_DEBUG_MISC=no Rebuild and you should find that the kernel is the normal and as expected size.........
  • Docker Swarm vs Kubernetes Comparison Guide


    A lot of companies are unsure which solution to choose and many may not be aware of Docker Swarm as an alternative to Kubernetes. One thing that many Sysadmins find is that Docker Swarm is simply easier, quicker to setup and maintain by far than Kubernetes.........
  • When is it time to leave your VPS/VDS Cloud Hosting Provider?


    When Is It Time to Leave Your VPS, VDS, and Dedicated Server Provider? Choosing the right hosting solution—be it Virtu........
  • Install Grafana on Linux Debian Ubuntu Tutorial Guide


    First we need a few extra packages: apt update apt install -y adduser libfontconfig1 musl sudo wget https://dl.grafana.com/enterprise/release/grafana-enterprise_10.3.1_amd64.deb Install / Enable Grafana dpkg -i grafana-enterprise_10.3.1_amd64.deb dpkg -i grafana-enterprise_10.3.1_amd64.deb (Reading database ... 44309 files and directories currently installed.) Preparin........
  • Linux how to get list of all timezones on system Ubuntu


    find /usr/share/zoneinfo/|sed s#"/usr/share/zoneinfo/"##g|grep "/"|grep -v posix|grep -v ^"Etc/"|grep -v ^right|grep -v ^"SystemV" Africa/Addis_Ababa Africa/Abidjan Africa/Blantyre Africa/Lusaka Africa/Casablanca Africa/Libreville Africa/Asmara Africa/Bujumbura Africa/Dakar Africa/Lagos Africa/Malabo Africa/Harare Africa/Kigali........
  • How To Upgrade Debian 8,9,10 to Debian 12 Bookworm


    Step 1.) Upgrade to Debian 11 first The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful. Step 2.) Update sources.list Update your /etc/apt/sources.list like this: deb http://........
  • apache2 httpd apache server will not start [pid 22449:tid 139972160445760] AH00052: child pid 23248 exit signal Aborted (6) solution Mint Debian Ubuntu Redhat


    If you get this error, it is often because you have configured Apache with modules that weren't actually installed. Eg. you try to load the PHPmodule but didn't actually install the apache2 php module, so the server can't start. In general, this error can often be caused by issues with problematic modules and/or Apache being configured for modules that have not actually be installed (eg. libapache2-mod-php) is missing. The above results in this less than obv........
  • How To Setup Python3 in Ubuntu Docker Image for AI Deep Learning


    The issue is that Docker images are stripped down, so many tools and even python3 is missing, so you'll have to build or update the actual image yourself. I assume you have started an image with something like this and that you have the Nvidia Toolkit installed (assuming you are using GPUs). If you're not using nvidia just remove --runtime=nvidia --gpus all. docker run -it --runtime=nvidia --gpus all ubuntu bash These works for most images li........
  • How to Configure NVIDIA GPUs with Docker on Ubuntu: A Comprehensive Guide for AI Deep Learning CUDA Solution


    Welcome to our in-depth guide on configuring NVIDIA GPUs with Docker on Ubuntu. This post is tailored for developers, data scientists, and IT professionals who are looking to leverage the power of NVIDIA's GPU acceleration within Docker containers. Whether you're working on machine lea........
  • How to upgrade to the latest Python version on Linux Ubuntu Debian Mint 3.11


    A lot of developers want to go to 3.11 because of the speed improvements, but most distros never have the latest Python version. Using the deadsnakes third party repo is the easiest way aside from compiling it yourself (which is safer and recommended): Step 1 - Add the repo apt-add-repository ppa:deadsnakes/ppa If you get an error about requests then install it:........
  • How to install and configure haproxy on Linux Ubuntu Debian


    haproxy is one of the best known and widely used Open Source load balancers out there and a strong competitor to nginx. haproxy is used by many large sites per Wikipedia: HAProxy is used by a number of high-profile websites including GoDaddy, GitHub,........
  • PXE-E23 Error BOOTx64.EFI GRUB booting is 0 bytes tftp pxe dhcp solution NBP filesize is 0 Bytes


    Be very careful about what filename you specify in dhcpd.conf if you get an error like this: NBP filesize is 0 Bytes PXE-E23:Client received TFTP error from server. If you specify "BOOTx64.efi" then the file had better not be called "BOOTx64.EFI" as it is case sensitive. It's really a case of th........
  • Virtualbox Best Networking Mode In Lab/Work Environment without using NAT Network or Bridged


    Virtualbox is a very powerful tool, but for some use cases it is less than optimal. Say you are in a work, lab or other environment where you are not alone on the physical network and there could be overlap of IPs, but you need all of your VMs to be contactable from your host, VMs need to communicate with each other, and VMs need internet. NAT Network will give you VM to VM communication and internet, however, it is buggy and unstable. It also doesn't allow host to VM co........
  • debootstrap how to install Ubuntu, Mint, Debian install


    In this example we install debian 10 with --variant=minbase which gives us a minimal/tiny install. Don't use variant if you want the full size install. mkdir /tmp/deb10files debootstrap --variant=minbase buster /tmp/deb10files/ Did you get an error? debootstrap --variant=minbase buster /home/theuser/VMs/deb10files/ You'll get this error if you make a directory in your home........
  • Nvidia Tesla GPUs K40/K80/M40/P40/P100/V100 at home/desktop hacking, cooling, powering, cable solutions Tutorial AIO Solutions


    Do you have access to some old Tesla GPUs and want to try them at home in your Desktop or old Server? Some people have wanted to try these units for gaming but keep in mind they have no video out port, they were only meant for AI applications such as Deep Learning. The easiest way by far is to choose an AIservice that has everything ready to go, perhaps with a bunch of Docker or Kubernetes containers. This can be done with Cloud services like Google, Amazon and many........
  • Stop ls in Linux Debian Mint CentOS Ubuntu from applying quotes around filenames and directory names


    Later versions of ls try to be helpful and smart to prevent errors in dealing with files with spaces that were tradtionally a pain. However if you need the raw/real filenames, this can break scripts or if you are pasting into a csv etc.... How do you make ls not add the quotes? Add the capital "-N" switch ls -N You could also add an alias to make it more permanent Do this to add it to ~/........
  • Cisco 2900 3900 Router Password Reset How To Reset Enable Password


    It is a bit different and annoying here for these types of routers/models as you need to physically remove the CF (Compact Flash) and only then, will it enter ROMMON mode (Ctrl + Pause remotely over the console will not do it for us). This means you cannot do this remotely, or at least not without the help of a remote/physical helper. Step 1.) Power off, router and remove CF Disk Slot#2 Go to the router and remove the slot#2 cover uses your hand or it may help to use a........
  • Translating "cisco" ...domain server (255.255.255.255) Cisco Router/Switch Solution


    If you are in enable mode and make a typo, the router will treat it as a domain name and try to resolve it, and if it can't resolve it, you'll have to wait until it times out. Here's how to solve the Translating domain server error in Cisco Enter this in config mode: no ip domain-lookup Be sure to sav........
  • Loaded: masked (Reason: Unit hostapd.service is masked.) Solution in Linux Debian Mint Ubuntu


    If you are getting this error from systemctl "Loaded: masked (Reason: Unit hostapd.service is masked.)" we need to unmask the service. Solution systemctl unmask hostapd Removed /etc/systemd/system/hostapd.service. It's fixed root@routerOS:/var/log# systemctl start hostapd root@routerOS:/var/log# systemctl status hostapd ● hostapd.service - Access point and authentication server for Wi-Fi and Ethern........
  • Ubuntu Mint Debian Howto Execute Command / Script / Program Upon Wakeup From Sleep


    Sometimes manual intervention on various Linux system's, including Debian, is required to fix things after waking up from sleep. One persistent issue is the sound system / pulseaudio needing to be reset and not working until you do that after waking up. It's not clear if it's an OS issue itself or the sound driver, but this will fix things. Where do we put scripts or commands that need to be used upon wakeup automatically? /lib/systemd/syst........
  • LightDM Mint Ubuntu Debian won't start errors Nvidia Graphics


    This error implies that there may be an issue with Xorg or maybe your NVIDIA GPU cannot start or initialize: 35 laptop kernel: [ 2031.857704] nvidia: loading out-of-tree module taints kernel. 35 laptop kernel: [ 2031.857724] nvidia: module license 'NVIDIA' taints kernel. 35 laptop kernel: [ 2031.857725] Disabling lock debugging due to kernel taint 35 laptop kernel: [ 2031.873280] nvidia: module verification failed: signature a........
  • How To Upgrade Linux Mint 18.2 to 18.3 to 19.x and 20.x


    Linux Mint offers an easy and painless upgrade path through the last 3 versions, which means no more reinstalling to stay current with the latest version. The only catch is that you need the latest of each version, so for 18, you need 18.3 before you can go to 19, and then 19.3 (or latest), until you go to 20. However, it's really a small price to pay and on the machines we've tested, the upgrade went seamlessly each time (although sometimes video drivers/custom kernel modules l........
  • How To Do Linux Network Bonding Teaming in Mint Debian Ubuntu


    Bonding is an excellent way to get both increased redundancy and throughput. It is similar to the "Network Teaming" feature in Windows. There are a few different modes but we will use mode 6, I think it's the best of both worlds, as it is not just a failover, but it provides round robin, so you will get redundancy and load balancing. So if you have a 1G single port, you will have a combined throughput of 4G at this point. Just bear in mind that the true thr........
  • LXC Containers LXD How to Install and Configure Tutorial Ubuntu Debian Mint


    If you are using mint, delete the preference that stops snap from installing (as it is required for lxc) sudo rm /etc/apt/preferences.d/nosnap.pref 1. Install lxd: sudo apt install lxd Issues install lxd or errors? Click here Debian at this time does not have lxd so you'll need to use snap: sudo apt in........
  • GlusterFS HowTo Tutorial For Distributed Storage in Docker, Kubernetes, LXC, KVM, Proxmox


    This can be used on almost anything, since Gluster is a userspace tool, based on FUSE. This means that all Gluster appears as to any application is just a directory. Applications don't need specific support for Gluster, so long as you can tell the application to use a certain directory for storage. One application can be for redundant and scaled storage, including for within Docker and Kubernetes, LXC, Proxmox, OpenStack, etc or just your image/web/video files or even da........
  • Ubuntu Mint audio output not working pulseaudio "pulseaudio[13710]: [pulseaudio] sink-input.c: Failed to create sink input: too many inputs per sink."


    If your audio is not working and you got this in your syslog: pulseaudio[13710]: [pulseaudio] sink-input.c: Failed to create sink input: too many inputs per sink. The issue is generally caused by too many audio inputs, or in other words you have too many applications that are hooked into pulseaudio. An easy and notorious offender is by having dozens of Firefox browser tabs open. Solution: Close all of your Firefox and the problem will........
  • 404 Not Found [IP: 151.101.194.132 80] apt update Debian 11 Bullseye Solution The repository 'http://security.debian.org bullseye/updates Release' does not have a Release file.


    This happens during an apt update and is related to an issue with sources.list, which is particularly troubling, if you are doing a "live-build". P: Configuring file /etc/apt/sources.list Hit:1 http://deb.debian.org/debian bullseye InRelease Get:2 http://deb.debian.org/debian bullseye-updates InRelease [39.4 kB........
  • (firefox:9562): LIBDBUSMENU-GLIB-WARNING **: Unable to get session bus: Failed to execute child process "dbus-launch" (No such file or directory) Solution


    (firefox:9562): LIBDBUSMENU-GLIB-WARNING **: Unable to get session bus: Failed to execute child process "dbus-launch" (No such file or directory) ExceptionHandler::GenerateDump cloned child 9743 ExceptionHandler::WaitForContinueSignal waiting for continue signal... ExceptionHandler::SendContinueSignalToChild sent continue signal to child [Parent 9562, Gecko_IOThread] WARNING: pipe error (40): Connection reset by peer: file /build/firefox-EymEXX/fire........
  • Debian Mint Ubuntu Which Package Provides missing top, ps and w Solution


    Install procps and it will install the other packages you need: apt install procps Reading package lists... Done Building dependency tree Reading state information... Done The following additional packages will be installed: libgpm2 libncurses6 libprocps7 lsb-base psmisc Suggested packages: gpm The following NEW packages will be ins........
  • How To Create OpenVPN Server for Secure Remote Corporate Access in Linux Debian/Mint/Ubuntu with client public key authentication


    Why choose OpenVPN instead of a firewall appliance? OpenVPN can be a reliable and easy replacement for traditional hardware or just be an additional tool that your company uses so that the firewall can focus on its job rather than acting as a VPNappliance at the same time. When comparing OpenVPN with traditional firewal........
  • ssh-keygen id_rsa private key howto remove the passphrase so no password is required and no encryption is used


    The key is that you need to know the passphrase to do it, if you don't know the password for the key then you can't remove the key since it cannot be decrypted. ssh-keygen is the easiest method and openssl can be used to manually remove the key and output it to a new file, which you can then copy back over top of the encrypted file. After that your public key authentication will work without any password prompt because it is no longer encrypted. Make sure you understand........
  • Ansible Tutorial - Playbook How To Install From Scratch and Deploy LAMP + Wordpress on Remote Server


    1. Let's work from an environment where we can install Ansible on. If you are using an older version of Linux based on Mint 18 or Ubuntu 16, you may want to get the PPA and get the latest version of Ansible that way: sudo apt install gpg sudo add-apt-repository ppa:ansible/ansible sudo apt update........
  • Linux Mint 20 cannot install snapd missing solution


    The Linux Mint team has disabled it by setting an apt preference, you can edit or just remove the file: sudo apt install snapd Reading package lists... Done Building dependency tree Reading state information... Done Package snapd is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source........
  • How to install Kubernetes with microk8s and deploy apps on Debian/Mint/Ubuntu Linux


    Kubernetes Easy Beginners Architecture Guide Kubernetes is known as container orchestration and we should start at explaining the container part of it. A Container is what runs the actual application and based on an Image, and are more comparable to something like an LXC Container, Virtuozzo/OpenVZ using the Linux Kernel Namespaces feature. Containers run these images as independent, isolated operating environments under the OS's exist........
  • Ubuntu/Debian Linux/Unix Howto Setup Install Syslinux Bootable USB with EFI and MBR from Command Line/CLI Terminal


    There aren't too many simple guides that show you how to use commands to setup your USB or other drive as a normal bootable drive where you can easily boot custom kernels or whatever OS you would like. 1. Get the tools we need: We install "syslinux" for MBR and "syslinux-efi" for EFI and "MBR" as we need a tool that embeds the actual MBR into our USB: sudo apt install syslinux syslinux-efi mbr........
  • Juniper JunOS Command Overview and Howtos Switch, Router, Firewall Tutorial Guide


    Enable "cli" mode equivalent in JunOS cli Configure Mode configure So rather than going to the console on a Cisco switch and typing "enable" and then "conf t", the equivalent in JunOS is "cli" and "configure". How Do You Apply Changes You've Made? You can make all kinds of changes to the switch, but remember they are not........
  • Linux how to compile binary with static sharedobjects embedded instead of dynamic to use on multi-distributions and avoid glibc compatiblity issues


    One simple flag to configure will create a makefile that statically links all the shared objects and embeds them instead the binary execute. This means as long as you have the same architecture that things should run. Eg. if you have an old version of Debian with a different version of glibc, then this will solve that problem. ./configure LDFLAGS="-static" To test that it is really statically linked run ldd: ldd src/wget........
  • Mikrotik RouterOS CHR/ISO Basic and Quick Setup Howto Guide


    Many people may not be aware that you can turn commodity hardware into a Mikrotik OS and there are various options which is "CHR" (Cloud Hosted Router) which is a VMimage meant for Virtualization only (seriously, I've tried to dd the image to a physical server and it just crashed as it does not contain any drivers for physical). One note as well if you are trying to do a baremetal install you may get an error "Error Loading Operating System" or........
  • CentOS 7 8 PXEBoot Netinstall Not Working Solution "Pane is dead "new value non-exisetnt xfs filesystem is not valid as a default fs type"


    The problem seems to be that whatever kernel and initrd you have is tied to an old version of CentOS 7 that is no longer in the current repos of most mirrors. If you were previously able to PXEboot and install CentOS and you are sure your network and tftp are good the problem is that you have an outdated kernel and initramfs that point to a defunct version.........
  • How To Replace Audio Track of Video using ffmpeg


    A very common use case is that you don't want to waste time using a video editor that requires you to open it up and manually import the video clip and audio clip, then manually delete the old audio track and import the video and new audio. That's too much work and time since we don't want to go through the hassle. ffmpeg is our solution, all we have to do is specify 3 variables and we're done! -i Windows2019-Server-Noaudio.mp4 is our in........
  • How To Password Reset, Recover, Bypass, Remove and Unlock on Windows 10,8,7,Vista,XP,NT,2000,2003,2008,2012,2016,2019 Administrative Login Programs


    If you've come here, don't be embarraassed, working in IT, this is the MOST common computer problem that almost everyone will encounter. The reason why I'm doing this post is because I've seen an increase from colleagues and admins having this problem and many times it's not even your fault. A common scenario is that someone acquires a new or used computer which they weren't given the password for. Fortunately Ihave a detailed list of all the options whether free or pa........
  • mdadm how to stop a check


    Is a mdadm check on your trusty software RAID array happening at the worst time and slowing down your server or NAS? cat /proc/mdstat Personalities : [raid1] [raid10] md127 : active raid10 sdb4[0] sda4[1] 897500672 blocks super 1.2 2 near-copies [2/2] [UU] [==========>..........] check = 50.4% (452485504/897500672) finish=15500.3min speed=478K/sec ........
  • How To Get Started on Ubuntu with gpt-2 OpenAI Text Prediction


    apt install software-properties-common add-apt-repository ppa:deadsnakes/ppa apt update apt install python3-pip apt install python3.7 curl gnupg python3.7-dev git ln -s /usr/bin/python3.7 /usr/bin/python3 pip3 install numpy keras_preprocessing curl https://bazel.build/bazel-release.pub.gpg | sudo apt-key add - echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | sudo tee /etc/apt/sources.list.d/bazel........
  • Remove cloud-init in your VM


    Unless you are using OpenStack, AWS etc then cloud-init is just some bloat that slows down the booting of your VMand can actually halt it from booting if it doesn't have a proper working IP (not good!). #remove cloud init! Debian based Ubuntu / Mint sudo apt remove cloud-init RHEL / CentOS based yum remove cloud-init ........
  • Linux Debian Ubuntu How To Install PEPPER Faster and Latest Adobe Flash Player in Firefox


    Just run this apt install command sudo apt install pepperflashplugin-nonfree browser-plugin-freshplayer-pepperflash After this restart your browser and check Adobe's site to verify if your Pepper flash is working and showing at least version 32. https://helpx.adobe.com/flash-player.html As you'll see below it will download the latest version which is currently 32 and this was not possible with the old/crappy deprecated adobe-flash plu........
  • How To Install NextCloud on Centos 7 and Centos 8


    yum -y install wget unzip wget https://download.nextcloud.com/server/releases/nextcloud-18.0.2.zip unzip nextcloud-18.0.2.zip yum -y install php php-mysqlnd php-json php-zip php-dom php-xml php-libxml php-mbstring php-gd mysql mysql-server Last metadata expiration check: 0:58:02 ago on Fri 13 Mar 2020 02:12:49 PM EDT. Dependencies resolved. ===================================================================........
  • ZTE Camera Cannot Work unable to connect to camera. Camera has been disabled becaue of security policies or is being used by other apps


    unable to connect to camera. Camera has been disabled becaue of security policies or is being used by other apps They say to do a factory reset but in some cases it doesn't work and the camera mysteriously just won't work so it appears to be a hardware error if that happens.........
  • How To Install OpenProject on Centos 7 Step-by-Step Guide


    There are a few caveats that may not be obvious to everyone so I am going to cover them here but keep this in mind before starting. Before starting install epel or you will be missing tesseract: yum -y install epel-release #1) When you specify your SSL certificate with a full path, it really needs to exist where you tell it to (including the default location of /etc/ssl/certs and /etc/ssl/c........
  • using Xvfb on virtual remote ssh server to have X graphical programs work


    The scenario here is that you have some sort of remote headless Linux server but would like to run some programs on them and get graphical access to them. The problem is that the remote server may be an image or VMwithout any virtual GPU and even if so, it is likely without KDE or Gnome, so there's no real way to do this, unless you follow our guide. Install xvfb apt install xvfb Reading package lists... D........
  • httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load modules/libphp5.so into server: /lib64/libresolv.so.2: symbol __h_errno, version GLIBC_PRIVATE not defined in file libc.s


    httpd: Syntax error on line 221 of /etc/httpd/conf/httpd.conf: Syntax error on line 6 of /etc/httpd/conf.d/php.conf: Cannot load modules/libphp5.so into server: /lib64/libresolv.so.2: symbol __h_errno, version GLIBC_PRIVATE not defined in file libc.so.6 with link time reference This is usually caused by a mismatch in OpenSSLversion. Interestingly enough a lot of times if it has happened during an update of your system, or after, usually just restarting httpd........
  • Radeon R3 GPU on Debian Crashing


    Occasionally my whole screen locks up and I cannot even swith to the console and I find this in my syslog: *-display description: VGA compatible controller product: Mullins [Radeon R3 Graphics] vendor: Advanced Micro Devices, Inc. [AMD/ATI]  ........
  • CentOS 8 how to convert to a bootable mdadm RAID software array


    The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array. Step#1 Install tools we need yum -y install mdadm rsync Step #2 Create your partitions on the drive that will be our RAID array Here I assume it is /dev........
  • ADATA USB Thumb Drive Issues


    This is the reason that I don't like the new ADATA USB drives such as the UV128/64GB or 128GB drives and other ones that look to be the same style (the green sliding USB connector). They just don't work well from new and never work properly at any point. [ 788.242463] usb 1-1.2: new high-speed USB device number 16 using ehci-pci [ 788.339816] usb 1-1.2: New USB device found, idVendor=125f, idProduct=db8a [ 7........
  • Ubuntu Debian Linux Mint r8169 r8168 Network Driver Problem and Solution


    This problem has been around forever, Linux seems to think it is fine to use the r8169 driver for an r8168 NIC but this often causes problems including the link not working at all. In my case ethttool shows the link up and detected but it simply does not work especially on a laptop that has been resumed from suspension. Sometimes it takes several minutes for it to work or to unplug and replug the ethernet. Here is the solution: Install th........
  • Linux Ubuntu Debian Centos How To Make a Bootable Windows 7, 8, 10, 2016, 2019 Server USB from ISO


    Use fdisk on your USB drive to create a bootable NTFS partition (in my case /dev/sdb): sudo fdisk /dev/sdb Welcome to fdisk (util-linux 2.27.1). Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Command (m for help): n Partition type p primary (0 primary, 0 extended, 4 free)........
  • How To Restore Windows MBR Bootsector from Linux using syslinux


    There are many ways but a favorite way is to boot any Linux LiveCD and to use the syslinux package like so: Just change the "sdx" to your sd for example /dev/sda or whatever the drive is that is supposed to boot Windows. sudo dd if=/usr/lib/syslinux/mbr/mbr.bin of=/dev/sdx 0+1 records in 0+1 records out 440 bytes copied, 0.0197808 s, 22.2 kB/s........
  • Linux Console Login Screen TTY Change Message


    This is all controlled by /etc/issue You can basically enter anything in there that you like, but there are preset variables that are mentioned at the end of the page that discuss this. Some examples of /etc/issue: Centos 7: S Kernel r on an m Ubuntu 16.04: Ubuntu 16.04.6 LTS n l You can also insert any of t........
  • Linux tftp listens on all interfaces and IPs by DEFAULT Security Risk Hole Solution


    Just edit your tftp file for xinetd like this: *Change the IPto be the IPof the interface you want to listen on. To test if your tftp is available on a certain IP range use nc -u yourip 69 to see if you can still connect (/var/log/messages or /var/log/syslog) should show the connection if it is open. Oct 13 23:20:34 01 xinetd[26631]: Started working: 1 available servic........
  • python import docx error


    sudo pip3 install python-docx [sudo] password for : Downloading/unpacking python-docx Downloading python-docx-0.8.10.tar.gz (5.5MB): 5.5MB downloaded Running setup.py (path:/tmp/pip_build_root/python-docx/setup.py) egg_info for package python-docx no previously-included directories found matching 'docs/.build' warning: no previously-included files matching '.DS_Store' foun........
  • Debian Ubuntu and Linux Mint Broken Kernel After Date - New Extra Module Naming Convention


    I don't consider a lot of these "extra" kernel modules "nice to have" as they often contain drivers for essential items like your soundcard, your NIC and many other devices that may not work. Sometimes you may find that "sound" or "ethernet" worked before a kernel/OS upgrade and now in the new version they don't. Often it will be because you need to install the "extra" kernel modules. One other weird thing is that sometimes........
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  • root/home directory has ownership changed to the wrong user/owner mysteriously


    Ifigured out what caused this but don't have the solution just yet. Iwould deploy a certain script from a .tar.gz to some servers and found that /root was always owned by user and group "1000.1000". This corresonded to the user who made the .tar.gz. For some reason when extract normally with "tar -zxvf file.tar.gz" it impacts the parent directories ownership. There must be some recursion going on or possibly the .tar.gz but I haven't f........
  • Centos 5 OpenSSL does not support TLS 1.2 Apache Error


    [Thu Jan 26 14:13:31 2017] [notice] caught SIGTERM, shutting down [Thu Jan 26 14:14:00 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Jan 26 14:14:00 2017] [error] Server certificate is expired: 'Server-Cert' [Thu Jan 26 14:14:00 2017] [notice] SSL FIPS mode disabled [Thu Jan 26 14:14:07 2017] [notice] suEXEC mechanism enabled (wrapper: /usr/sbin/suexec) [Thu Jan 26 14:14:07 2017] [error] Server certificate is expired: 'Server-Ce........
  • How to Properly Secure SSL/TLS Apache Settings against Heartbleed Poodle (TLS) Poodle (SSLv3) FREAK BEAST CRIME


    Many users still are not aware but simply patching OpenSSL does not secure you against many known and easy to exploit attacks that will render your encryption useless by an attacker. Use the following setings in /etc/httpd/conf.d/ssl.conf SSLCipherSuite "EECDH+ECDSA+AESGCM EECDH+aRSA+AESGCM EECDH+ECDSA+SHA384 EECDH+ECDSA+SHA256 EECDH+aRSA+SHA384 EECDH+aRSA+SHA256 EECDH EDH+aRSA !CAMELLIA !SEED !3DES !RC4 !aNULL !eNULL !LOW !MD5 !EXP !PSK !........
  • ADATA SU800 256GB 3D NAND Flash SSD Test & Review


    I keep reading these drives are slower, but they are cheap and still SSDand work very fast for my needs. As you can see the sequential read is 481-491MB/s, if I put them in MDADM RAID10 mode (normal RAID1) they should give me well over 900MB/s and with redundancy and being very cheap for what they offer. [1232206.315622] scsi 8:0:1:0: Direct-Access ATA ADATA SU800&........
  • Linux Mint 17 How to Enable File Sharing Option in File Manager


    I still cannot understand how this would not be enabled by default and I struggled to find the reason why with manually installing samba etc.. wondering why the option for sharing was not in the menu. On Linux Mint "MATE" the package is called "caja-share" and on Cinnamon it is called "nemo-share" so edit the below command as necessary: *Also note that the "samba" package is necessary as it is not inst........
  • blocked for more than 120 seconds issues with iowait and timeout on Live Linux distribution while writing to physical disk


    This happened while an mdadm array was syncing, all access from writing a new blank file to opening a small .txt file was very slow: [222117.312078] kjournald starting. Commit interval 5 seconds [222117.685060] EXT3-fs (md0): using internal journal [222117.685096] EXT3-fs (md0): mounted filesystem with ordered data mode [222122.376847] kjournald starting. Commit interval 5 seconds [222122.602825] EXT3-fs (md2): using internal jour........
  • astrachat connection problems in Android 5.01 Lollipop


    I wanted to use Astrachat because it seems to be the only app that has video, pic and file sharing for Jabber butI cannot even connect despite any other client working fine including Xabber and others. astrachat "Oops.. We can't connect to the account that you provide above. Please recheck your account detail". Unfortunately to make it worse there doesn't seem to be any error log or more details about the issue. The jab........
  • sed how to avoid escaping


    sed gets to be a pain and a real mess and is hard to read and understand when you have to escape things like / etc. Idid not realize until recently that you don't need to use / as a separator, you can use virtually any non letter or number character. Eg we have used # as the separator to avoid having to escape the forward slashes and in this way the command is plain, easy to understand, edit and saves time/hassle without the need for escaping. sed -i s#http........
  • mysql_real_escape_string returns an empty string solution


    This is a common mistake but many people do not realize this function comes from mysql itself, so therefore you need an active mysql connection open. Usually the string will be empty and null when you call it from outside of the database connection portion of your code. eg. an example of the wrong way and creating a null/empty string $var = mysql_real_escape_string($myself) mysql_connect(); // returns n........
  • Centos and obfsproxy install errors


    pip install obfsproxy /usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. InsecurePlatformWarning You are using pip version 7.1.0, however version 8.1.1 i........
  • curl: (35) SSL connect error solution


    curl -k https://somesite.org curl: (35) SSL connect error The site used to work until I got a new SSL cert Updating curl with (yum -y install curl) made it work again. ........
  • Apache SSL Reverse Proxy Very Slow Solution


    This is a simple fix but not a simple problem and it still doesn't make sense to me. But in a nutshell if your target proxy server works fast when accessing directly over SSL then this may be your issue. It seems SSL does not play nicely when the target proxy destination/host has a riduculously long key (such as 8192 bits long). Now this is normally not a problem, in fact the target server could be accessed with hardly any delay directly despite such a long key.........
  • esniper error on Linux Mint 17.2 Debian/Ubuntu: Cannot connect to URL : SSL connect error: gnutls_handshake() failed: Illegal parameter Retrying... esniper encountered a bug. It looks like your esniper version is not current. You have version 2.28


    Auction 262382440107: Cannot connect to URL : SSL connect error: gnutls_handshake() failed: Illegal parameter Retrying... esniper encountered a bug. It looks like your esniper version is not current. You have version 2.28.0, the newest version is 2.31.0. Please go to http://esniper.sf.net/ and update your copy of esniper.........
  • Nvidia Linux Card not working due to LSI 9200/SAS2008 IRQ conflict


    At first my BIOS said the card may not work right because there is no more option ROM space. I disabled the Option ROM for both LSI 1068 and 2008 chipsets, Network Boot ROM and most other PCI slots, Serial Port, etc... and the message went away but the card still does not work properly. But it still cannot initialize the card properly(does not work): [ 33.943272] NVRM: This PCI I/O region assigned to your NVIDIA device is invalid:........
  • Apache Vhost HowTo Serve Same Content using a different domain and IP


    There are a few ways of doing this and all basically involve using the reverse proxy or "ProxyPass" feature of Apache to accomplish it. 1.) Create a normal vhost and simply symlink the root directory of the site you want to mirror. Eg. originalsite.com and newsite.com /vhosts/originalsite.com/httpdocs You would symlink like this: ln -s /vhosts/originalsite.com/httpdocs vhosts/originalsite.com/........
  • MySQL PHP adding a backslash/escaping apostrophes Solution


    The first thing to diagnose is what is actually in the database (use PHPMyAdmin or CLI). You will of course either find that the backslash is either in the database or not. If the backslash is in the database you probably have magic quotes gpc/runtime on and/or are calling the "addslashes()" function which does this. If you are escaping your data with mysql_real_escape_string() then think again, you probably have magic quotes gpc enabled either in php.ini or........
  • Linux Mint/Ubuntu/Debian Dual NICs networks problem when enabling and disabling one device


    The Scenario You have dual NICs and you disable NIC1 which uses 192.168.1.1 as its gateway. With NIC2 you enable it/connect it to another network which also has the gateway 192.168.1.1 Everything will work fine at this point. When switching back to NIC1 even with NIC2 disabled and even unplugged, the OS basically can't pick up the new/updated ARP entry of the old device for 192.168.1.1 and perhaps thinks it is a security risk or spoof of some sorts and blocks i........
  • Force SSL for all URLs Apache htaccess modrewrite


    The best way is as below in .htaccess using modrewrite, any request that is not SSL will be redirected to https://domain.com and the exact same URL RewriteCond %{SERVER_PORT} 80 RewriteRule ^(.*)$ https://domain.com/$1 [R=301,L]........
  • Mount a SMB Samba share in fstab Linux Debian/Ubuntu/Centos


    Add the following to fstab where 192.168.1.125/Media is the samba share and where /home/homeuser/Downloads is where you want to mount. Change user and pass to what is needed (if no pass is required it still works fine with the below). //192.168.1.125/Media /home/homeuser/Downloads cifs user=guest,pass=bla 0 0 mount: wrong fs type, bad option, bad superblock on //192.168.1.125/Media, &nbs........
  • Avocent 8020 KVM Java Icedtea Viewer


    This command in Debian/Ubuntu/Mint will get everything need installed for most Java based KVM viewers: sudo apt install icedtea-netx The following additional packages will be installed: ca-certificates-java icedtea-netx-common openjdk-8-jre openjdk-8-jre-headless It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post.........
  • CPanel SNI error


    Your server does not support SNI, so all of your SSL websites must use the same SSL certificate. An update to the certificate on an existing SSL website will affect all of your SSL websites, and new SSL websites must use the currently installed certificate.........
  • openvz yum problem Centos 6.5 cannot find file on mirror:


    #solution Edit /etc/yum.repos.d/openvz.repo For the first two entries comment out #mirrorlist and uncomment #baseurl and then it worked openvz yum problem Centos 6.5 cannot find file on mirror: yum update Loaded plugins: fastestmirror Determining fastest mirrors * openvz-kernel-rhel6: mirrors.ustc.edu.cn * openvz-utils: mirrors.ustc.edu.cn base ........
  • Virtualbox errors on Ubuntu/Debian/Mint


    The solution was to reinstall the vbox dkms package and do a manual modprobe of the modules it makes. I never sorted out the unable to start due to the USB issue, I did have the guest additions installed but the only way to boot was to change the pointing device from USB to PS2 and then to disable the USB controller (if your pointing device is set as USB, disabling USB will not work because it will re-enable by default when it sees your pointing device is USB, this is w........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    sudo apt-get install zoneminder [sudo] password for one: Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: libuser-perl python-evince kdebase-apps kwrite unixodbc libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp python-mediaprof........
  • ssh session and port forward or reverse port matching or assocation howto


    Use netstat with the -anpe option. The e option shows the inodes and I do not know if it will always work or if it was by fluke but I was dealing with dozens of SSHsessions and needed to know which session was related to which forward (the PIDs of the SSHand SSHD did not match etc...) Notice the "59560675" and "59560762" those are almost identical, if you find two sets that are nearly identical except for the last 3 digits they may match (in my ca........
  • ECC Errors in action


    Message from syslogd@server at Sep 14 11:35:59 ... kernel:[Hardware Error]: MC4 Error (node 1): DRAM ECC error detected on the NB. Message from syslogd@server at Sep 14 11:35:59 ... kernel:[Hardware Error]: Error Status: Corrected error, no action required. Message from syslogd@server at Sep 14 11:35:59 ... kernel:[Hardware Error]: CPU:6 (10:8:0) MC4_STATUS[Over|CE|MiscV|-|AddrV|CECC]: 0xdc00400021080813........
  • Dell CS24 NV5/NV7 Gigabyte GA-3CESL-RH Motherboard ROM Chip info


    If you remove the white label on the chip (near the CMOS battery) you will find the following details about it: SST 49LF080A 33-4C-NHE It is the PLCC32 type and can be pried and removed safely (but be very careful) with an eye glass flat head screw driver. If you just have a bad flash you may be able to reprogram your original or just buy another one with the part# above and reprogram it. This is great news for people who have bricked th........
  • Dell CS24-NV7 lspci dmidecode info


    0000:00:00.0 RAM memory: NVIDIA Corporation MCP55 Memory Controller (rev a2) 0000:00:01.0 ISA bridge: NVIDIA Corporation MCP55 LPC Bridge (rev a3) 0000:00:01.1 SMBus: NVIDIA Corporation MCP55 SMBus (rev a3) 0000:00:02.0 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a1) 0000:00:02.1 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a2) 0000:00:05.0 IDE interface: NVIDIA Corporation MCP55 SATA Controller (rev a3) 0000:00:05.1 I........
  • Dell CS24,FS12 NV5 and NV7 1U Server Information & Parts


    Motherboard: Gigabyte GA-3CESL: http://b2b.gigabyte.com/products/product-page.aspx?pid=2658#dl Dell Part Numbers for the motherboard: R1232 R1232L R2232S SERVER MOTHERBOARD GENUINE 408P9 CN-0408P9 GA-3CESL Manual Download here RAMSlots: 16 (8 controlled by each CPU) RAMType: DDR2 ECC 5300P........
  • Unable to configure RSA server private key SSL Library Error: 185073780 error:0B080074:x509 certificate routines:X509_check_private_key:key values mismatch


    [Tue Jun 23 02:05:52 2015] [error] Unable to configure RSA server private key [Tue Jun 23 02:05:52 2015] [error] SSL Library Error: 185073780 error:0B080074:x509 certificate routines:X509_check_private_key:key values mismatch The above is an accurate description of what is wrong. In our case the client made a simple mistake of thinking the localhost.crt and localhost.key (default key locations for Apache SSL in Centos) were in the same directory but they we........
  • Error code: ssl_error_rx_record_too_long


    An error occurred during a connection to site.com. SSL received a record that exceeded the maximum permissible length. (Error code: ssl_error_rx_record_too_long) The page you are trying to view cannot be shown because the authenticity of the received data could not be verified. Please contact the website owners to inform them of this problem. When the above happens in our experience it is a misconfiguration of........
  • dir2slideshow Centos rpm requirements


    yum -y install dvdauthor ffmpeg mjpegtools sox bc rpm -ivh dvd-slideshow-0.8.4-2.noarch.rpm Preparing... ########################################### [100%] 1:dvd-slideshow ########################################### [100%] /usr/bin/dir2slideshow: line 553: bc: command not f........
  • Windows 2012 Server R2 Install Error "windows cannot find the microsoft license terms windows 2012 server install"


    windows cannot find the microsoft license terms windows 2012 server install This is actually because you are using less than 576MB of RAM. In my case I was installing on a KVM VPS with 512MB of RAM. This issue would apply to any physical or virtual server with less than 576MB of RAM. This includes Virtualized VPS Servers with XENHVM, KVM, VBOX, VMWare etc.. or Dedicated Servers with such little RAM. It's very misleading of course since it has not........
  • Flash slowing down your Firefox browser? Install Flashblock plugin


    Install the "Flashblock" plugin because we all know most unwanted high CPU usage situations come from the browser usually because of a looping Flash ad taking up 100% CPU. The solution is to install the "Flashblock" plugin that doesn't allow any Flash to load and play unless you click on the placeholder.........
  • cPanel How to set SSL and Dedicated IP in cPanel


    Account Functions -> Change Site's IP Address Choose the domain and then click "Change" Choose the new IP 1.) Setup SSL Certificate in cPanel Click on "SSL/TLS Manager" under the "Security" section. 2.) Under " Private Keys (KEY)" Click "Generate, view, upload, or delete your private keys." Choose "Key Size: 4096........
  • OpenVZ vzctl update changes how iptables work - iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. updated solution


    Are you getting the same old error message even though your iptables settings for OpenVZ are correct? iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. The reason is because in newer vzctl the old way of setting IPTABLES="" in vz.conf is completely deprecated (I spent some time fiddling wondering why my settings were correct but........
  • libguestfs tools howto guide for mounting partitions and managing virtual machine images


    libguestfs tools howto guide for managing virtual machine images. libguestfs-tools aka guestfs tools has a lot of tools that make this very easy for you. You can easily mount partitons from an image with some of the commands below. To mount a partition #mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount" guestmount -a kvmuser102821.img -m /dev/sda1 mount ........
  • Directadmin compile error solution cc: Internal error: Killed (program cc1)


    cc: Internal error: Killed (program cc1) Please submit a full bug report. See for instructions. make: *** [ext/fileinfo/libmagic/apprentice.lo] Error 1 make: *** Waiting for unfinished jobs.... Stopping crond: ........
  • Postfix Errors & Solutions "unprivileged": bad value: "???" - bad transport type:


    Aug 25 16:43:24 evohostingtor postfix/master[19471]: fatal: /etc/postfix/master.cf: line 24: field "unprivileged": bad value: "???" Solution: I had the wrong thick dashes when c&ping (just retype them with your keyboard) Aug 25 16:47:10 mailbox postfix/master[24498]: fatal: /etc/postfix/master.cf: line 25: bad transport type: syslog_name=postfix/auth-cleanup auth-cleanup unix n - - - 0 cleanup #-o syslog_name=postfix/........
  • Windows 2019 2016 2012 2008 Server Trial How To Activate & Extend the Trial


    To activate your Windows server trial which gives you 180 days: Start ->Right Click (My Computer). Click "Activate Windows now" To renew your license for 180 days (can be done 6 times): Start -> Type this command: slmgr.vbs -rearm Wait a few minutes until it says it is successful (unless you get that message it has not worked or been done)........
  • Asterisk VOIP Sipura/Linksys PAP2T Calls Not Being Received Solution


    This problem seemed to happen recently but was likely causing issues before where the phone(s) do not ring. Now there are a few reasons why this can happen especially if your adapter has DND mode enabled (disable it). However that wasn't my issue and Ionly figured it out the other day when by fluke if you're on the phone (making a call) then calls will come in. That's when Ifigured out the solution: This likely app........
  • yum Centos 386 and 64 bit conflict resolution


    This can happen when you install RPMForge or other repos with the wrong architecture and here's how you fix it (simply uninstalling won't usually fix it): solution yum clean all yum -y install openvpn Loaded plugins: fastestmirror, presto Loading mirror speeds from cached hostfile * base: mirror.its.sfu.ca * extras: centos.mirror.nexicom.net * rpmforge: mirror.cpsc.ucalgary.ca * up........
  • Directadmin Install Error Cannot find /usr/include/openssl/ssl.h. Did you run the pre-install commands?


    Cannot find /usr/include/openssl/ssl.h. Did you run the pre-install commands? http://help.directadmin.com/item.php?id=354 yum -y install openssl*........
  • [Hardware Error]: CPU:0 MC4_STATUS[-|CE|MiscV|-|AddrV|CECC]: 0x9c054c84011c011b [Hardware Error]: cache level: L3/GEN, tx: GEN, mem-tx: RD [Hardware Error]: Northbridge Error (node 0): L3 data cache ECC error.


    This server has been running for weeks without issue, it's currently only using 1 of 2 CPUs as it is running in the office as a test bed (mainly due to the handle 12 bay storage/great for testing HDDs). The errors below seem to mainly be from AMD CPUs, it's only happened a single time and in the days since Igot that error it hasn't occurrred. Interestingly enough /proc/cpuinfo still shows all 4 cores of the CPU (Opteron 2373 Quadcore HE) and the functionality doesn't seem........
  • Fatal error: Out of memory (allocated 6291456) (tried to allocate 7680 bytes)


    Fatal error: Out of memory (allocated 6291456) (tried to allocate 7680 bytes) This is usually caused by Wordpress, Drupal or other ridiculously inefficient CMS' out there, as a temporary fix you can increase PHP's memory limit but it's best to find the actual culprit, by disabling add-ons and other scripts etc...........
  • Dell CS24-NV7 Howto Enable LAN/NICs and PXEBoot in the BIOS


    Dell CS24-NV7 Unusually the Virtualization was enabled when I got this server but all the NICs were diabled in the BIOS including PXE boot! Advanced -> Advanced Chipset Control PCI Slot 1 Option ROM: Enabled Onboard LAN1 Control: Enabled LAN1 Option ROM Scan: Enabled (you need it for PXE boot) Onboard LAN2 Control: Enabled LAN2 Option ROM Scan: Enabled *you will need to reboot and........
  • mdadm how to add additional RAID 1 drives


    This is a great way to upgrade your RAID array or move it/copy it to a new set of hard drives. Eg. you have a current RAID 1 array on older/slower drives. Just add at least 1 of the new drives to the array, update grub/install it and then boot into it. Then you have a transparent data migration that is fully synchronized. mdadm --grow /dev/md126 --raid-devices 3 md127 : active raid1 sdc1........
  • Apache SNI is not needed what is the issue?


    Iread this article and still don't understand the issue. If I understand correctly the client negotiates after the first SSLconnection and then gets the correct hostname and thus correct certificate. http://wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI To their credit I know I'm not using SNIbecuase Iget this message in the Apache log :) [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! B........
  • Unixbench Testing


    The first is a dual CPU AMD Opteron 2373EE (4 cores x 2) and I think it did bad because it has some old 250GB SATAs which can only do about 65MB/s max sequential reads. I think it should have blown away the second (AMD X4 640 Quad Core). [root@fs12home unixbench-4.1.0-wht-2]# ./Run make all make[1]: Entering directory `/root/unixbench-4.1.0-wht-2' Checking distribution of files ./pgms exists ./src exists........
  • Dell FS12-NV7 2U Server Information and Guide


    I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards. My particular model came with the following: 2U Rack Mount Server with Rails 2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times) 16GB RAM 2 x 250GB Seagate SATA 2 x Dell Perc 6/i (horrible and a nightmare to work........
  • Dell Perc 6/i SATA benchmarks without battery


    The results are not bad, the Hitachi performs the same as it does in a SATA2 motherboard. However, the 2TB is much different, on a similar 2TB Toshiba I get about 198MB/s on a different motherboard vs the 2TB Hitachi which should produce similar results. This Dell Perc 6/i is on a PCI x8 riser card and is connected to a 12-port backplane. Adapter #0 Enclosure Device ID: 32 Slot Number: 0 Enclosure position: N/A De........
  • Dell Perci 6/i Firmware Upgrade Guide Tutorial


    One thing to remember is that you need MegaCli to do the flashing. You also need the correct file,I tried at least 2 different Perc 6 firmwares from Dell that kept getting rejected as corrupt by MegaCli(they were really the wrong version). I have an external PCI-E Dell 6 Perc/I butI chose images from the 'Integrated" on motherboard version as it was allI could find. They are different, and below is my first time finding success.........
  • Dell Perc 6/i cannot downgrade


    I flashed an LSI Logic firmware to it and it broke the BIOS (cannot do Ctrl+R) for booting purposes but allows other functionality to work normally. I tried downgrading to a Dell firmware for Perc 6i but it won't work, not even with MegaCli wget http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN --2013-08-26 12:53:39-- http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN Resolvi........
  • LSI MegaRAID Adventures, Guide and HowTo


    LSi Megaraid At first it was configured as a RAID 0, then I deleted the Virtual Disk Group. I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing. To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group. In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
  • pxe-32 tftp open timeout


    pxe-32 tftp open timeout The solution was to enable tftp in xinetd with "chkconfig tftp on". See the troubleshooting below: chkconfig --list NetworkManager 0:off 1:off 2:off 3:off 4:off 5:off 6:off acpid 0:off&n........
  • Bash weird variable whitespace missing when echoing printing


    Bash weird variable whitespace missing var=`cat tlds.csv|grep .ca,` # echo "var=:$var:" :ar=:.ca,Canada Why is the v missing in the last line? It should be :var=:.ca,Canada instead of :ar=:.ca,Canada I noticed a problem with the file with doing a "cat -v" on it. Here's the issue, the file contains carat M ^M: .vg,British Virgin Island........
  • mkdir(): Too Many Links - The Solution and Problem in ext3 filesystems


    The error itself "mkdir(): Too Many Links" is not very useful, but I'll translate it into plain English. It means you've reached the filesystem's limit of how many directories can be created in a single directory. In this case for ext3 the limit is 32000 and it was exceeded. What's the solution? The simple solution is to move those directories into more subdirectories possibly sorting them by date, alphabet or numerically.........
  • find only directory names in Linux


    find / -name 'thedirectorytofind' -type d That's all there is to it and now you don't have to get a listing of all the files along with it. Another cleaner solution that supports wildcards is the following find prep-*/dvd-slideshow_temp*/ -type d ........
  • Apache SSL Change Default SSL Vhost and Listening Port for SSL


    vi /etc/httpd/conf.d/ssl.conf Change the following from "Listen 443" to something like below Listen 2243 Then find the SSLVirtual Host Context and edit like below (to your new listening port) ## ## SSL Virtual Host Context ## ........
  • Country List Names in HTML Select From


    This is useful for developing a lot of applications, I'm putting it here to keep it handy for myself and hopefully others: Choose CountryCanadaJapanUnited StatesUnited KingdomAfghanistan........
  • postfix/dovecot Sent emails missing sometimes


    On occassion and from a variety of networks and clients, Sent messages don't get saved. I'm wondering if these log messages could be why: May 3 14:16:39 mail.box postfix/smtpd[5195]: connect from 192.168.1.58 May 3 14:16:39 mail.box postfix/smtpd[5195]: SSL_accept error from 192.168.1.58: -1 May 3 14:16:39 mail.box postfix/smtpd[5195]: lost connection after CONNECT from 192.168.1.58 May 3 14:16:39 mail.box postfix/smtpd[5195]:........
  • SSH Can't Login/Hang


    Client Log OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to 192.168.1.253 [192.168.1.253] port 22. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/identity type -1 debug1: identity file /root/.ssh/id_rsa type 1 debug1: identity file /root/.ssh/id_d........
  • Directadmin Log File Locations


    This is a handy link and list of all the relevant Directadmin log files and related servers. http://help.directadmin.com/item.php?id=11 DirectAdmin: /var/log/directadmin/error.log /var/log/directadmin/errortaskq.log /var/log/directadmin/system.log /var/log/directadmin/security.log Apache:........
  • Directadmin error/** Found 7 pre-existing rpmdb problem(s), 'yum check' output follows: e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of e2fsprogs-libs = ('0', '1.41.12', '3.el6') e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of l


    Solution To The Following: yum -y install zlib-devel yum -y install e2fsprogs* *** Cannot find /usr/include/et/com_err.h. (yum install libcom_err-devel) *** Installation didn't pass, halting install. Once requirements are met, run the following to continue the install: cd /usr/local/directadmin/scripts ./install.sh Common pre-install commands: http://help.directadmin.com/it........
  • Bad Hard Drive Slows Down Computer


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  • Intel's Finnish Fetish


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  • pound a Linux Load Balance and Reverse Proxy


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  • Create/Enable SSL Certificates for Apache on Linux/Unix Systems eg. Redhat,Centos,Debian


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  • Clustered/Distributed Network Filesystems, Which Ones live up to the hype?


    I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems. DRBD I first started off with DRBD and Ihave to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........
  • Unixbench Score with Glusterfs/Openvz & Quad Core Xeon - Updated with GlusterFS 2.0.8


    You might remember my original GluserFS/OpenVZ benchmark which produced a horrible 29.8 This is the exact same system, but using the latest 2.0.8 (with some small files patch which speeds up performance) you can see it is about 25% faster. I also haven't tuned my config files at all, but there are some settings that should increase performance on small files which I believe i........
  • Tyan S2735-8M Maximum Hard Drive Limit/Not Working/Doesn't work with 1TB 1000GB hard drives


    Inever saved any of the logs, but basically no matter what OS (Linux)I used, I could not get my 1000GB hard drive to work (Seagate SATA). The BIOS recognizes the drive and fdisk -l shows the hard drive as it should. The tricky thing is that different OS's will give you different results, but don't be fooled. You can't use these larger drives for long. Iwas getting all kinds of seek/IOerrors and also messages that the port could not be read.........
  • Unixbench Score with Glusterfs/Openvz & Quad Core Xeon


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  • [error] server reached MaxClients setting, consider raising the MaxClients setting - Apache


    Have you ever seen this dreaded message in your Apache/HTTPD /var/log/httpd/error_log? [error] server reached MaxClients setting, consider raising the MaxClients setting The error itself is slightly misleading. Ibelieve this happened to one of my servers, I found Apache was running still, and that you could telnet to port 80 but no respnose would be given. For some reason my error log initially did not have the above error, but after a restart I saw........
  • iPhone 3GS Jailbreak Information & Benefits


    Truly, the only way to unleash the capabilities and customization abilities of iPhone are to jailbreak, it's not just for hackers anymore. A few days ago someone by the named of "geohot" released a single click application called "purplera1n", which does the entire operation smoothly and seamlessly. In our case, the first time it went as far as "done, wait for reboot" on our Windows machine and for minutes we waited and saw the pic on the iPhone w........
  • iPhone has no password/wand manager saving feature in Safari Web Browser


    I kind of expected this feature to be there in some form, to stay ahead of the pack Apple needs to stay on top of this. User's of HTC's Android smart phone which uses a Linux based OS with Google's power behind it, note that you can save passwords in the browser on that phone. Apple needs to continuously evaluate the needs in its core apps and make sure the features are cutting edge and top notch, if other phones come out with some of these seemingly small but essential features........
  • Weird characters in Linux putty shell


    Iused to get all kinds of weird annoying characters like "" during compilation with gcc especially. example: dmg2img.c:456: error: BZ_OK undeclared (first use in this function) dmg2img.c:471: warning: implicit declaration of function BZ2_bzCompressEnd dmg2img.c:482: warning: implicit declaration of function BZ2_bzDecompress dmg2img.c:484: error: BZ_PARAM_ERROR undecl........
  • Using a Mac OSX DMG Image in Windows and Converting to Standard ISO Format use dmg2iso


    The dmg format is silly and annoying to work with, why couldn't Apple stick with the .iso standard? Anyway, there's an excellent Linux and Windows based tool to convert it back to a normal .iso Image called dmg2iso I'll only cover theLinux version although the Windows pre-built binary works the same way. Download dmg2iso here for free (from the author's website) It's just silly and doesn't make sense that Ubuntu doe........
  • Apple iPhone 3GS and predecessors are leading a revolution


    As much of a computer nerd as Iam, I'm usually a late adopter to technology for a few reasons. Ifeel most new hyped technologies and electronics are mainly fads, and I'm also cheap. Adopting later means you avoid the bugs, kinks and most importantly pay the lowest price, that's me being cheap again :) I never read much about the iPhone but Isaw all the hype around it and until recently I wasn't a big fan of anything Apple until a few years ago I realize........
  • OCFS2 crash


    When trying to even cd or ls the mounted OCFS2 partition it crashes. Ithink this is a combination of VMWare Server's problem and the way I mounted and symlinked to it. More than anything this shows the problem and lack of forsight with VMWare, but also that OCFS2 is easily crashed if you do strange things. Output of /var/log/messages for OCFS2 Apr 10 15:57:45 localhost kernel: [84331.691258] Modules linked in: vmnet vmci vmmon ocfs2_stac........
  • Configuring OCFS2 Clustered File System on Debian Based Linux including Ubuntu and Kubuntu


    There's a lot of information and guides on OCFS2 for RHELand Centos Linux but the package setup and configuration is slightly different and this has thrown some people off. Installing OC2FS You should install the following packages to get started: apt-get install ocfs2-tools ocfs2console Configure OC2FS In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb However in Debian based Linux it is located........
  • Viewing and Connecting to an SMB Samba Share on Windows/Linux/Unix


    This will give you the basic info needed to browse and connect to Samba shares from the command line. From the GUI of Gnome or KDE etc, it is pretty standard and straight forward. However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go. First get a list of all the Samba/SMB shares on the target. smbclient -L hostname........
  • Rackable Systems and their Microslice Clustered 1U Servers


    Ithink there has been a lot of negative press towards Rackable Systems. We will give their new solution credit that it is marketed very well, and comes prepackaged and ready to go. But let's cut through the hype of both sides, the people who love this concept and the people who hate it. What Rackable Systems have done is a first, to minimize space, power and costs into small servers. This is great, and many companies have already built their own servers based........
  • Bash Scripting Variable Scope Using Piped While Loop


    I've been struggling with this for awhile, wondering why all of my variables are null. Ijust realized the variables disappear after leaving this while loop. Note that I'm piping to the while loop which makes a subshell Ibelieve which is the cause of the issue: echo "$accounts"|while read thisline; do somevariable="some value" (( ++counter )) done At all costs you ne........
  • Writing/Burning a data CD-R/DVD-R or DVD+RW in Unix/Linux


    There's a lot of outdated information and confusion for system administrator's out there. One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle. At a later date we'll cover how scripting can automatically backup certain........
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