• nvidia cannot resume from sleep Comm: nvidia-sleep.sh Tainted: Linux Ubuntu Mint Debian


    This seems to happen in many different drivers but it happened more often in newer versions such as 530 vs 525. Then nvidia-modeset goes to 100% There are many reports of this appearing since driver 4.70 and I can confirm I've seen this in various machines. https://forums.de........
  • 2024 Buyer's Guide: How to Choose and Buy the Best VPS/VDS for Your Needs - Tips and Strategies


    In today’s digital landscape, finding a reliable and secure Virtual Private Server (VPS) or Virtual Dedicated Server (VDS) goes beyond just comparing specs and prices. With increasing concerns over data privacy, security breaches, and government surveillance, the wisdom of choosing your VPS/VDS provider based on juri........
  • 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://........
  • 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........
  • Linux Ubuntu Mint how to check nameservers when /etc/resolv.conf disabled solution


    You'll notice that /etc/resolv.conf contains dire warners on most Linux Desktops. # This file is managed by man:systemd-resolved(8). Do not edit. # # This is a dynamic resolv.conf file for connecting local clients to the # internal DNS stub resolver of systemd-resolved. This file lists all # configured search domains. # # Run "resolvectl status" to see details about the uplink DNS servers # currently in use........
  • talib/_ta_lib.c:747:10: fatal error: ta-lib/ta_defs.h: No such file or directory


    If you are installing ta-lib for Python and get this error then you can normally solve it by manually getting the ta-lib source files and compiling. tar -zxvf ta-lib-0.4.0-src.tar.gz cd ta-lib;./configure;make;make install Collecting ta-lib Downloading https://files.pythonhosted.org/packages/39/6f/6acaee2eac6afb2cc6a2adcb294080577f9983fbd2726395b9047c4e13ec/TA-Lib-0.4.26.tar.gz (272kB) &nbs........
  • How to install Windows or other OS and then bring to another computer by using a physical drive and Virtual Machine with QEMU


    This has been a tried and true method for Windows because it is finicky with hardware changes without a reinstall (eg BSOD on boot is what happens 9/10 times unless you move to the same hardwar). Surprisingly, if you use a QEMU VM and do a standard install, it has worked in every system I've thrown the drive in afterwards. So the play is this, use a USB SSD, physical SATA drive plugged internally or for convenience, you could use a SATA to USB adapter on another computer to perf........
  • 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........
  • iptables NAT how to enable PPTP in newer Debian/Ubuntu/Mint Kernels Linux


    Remember that control connections are established on port 1723 and then actual data is transferred over GRE protocol 47. If you have a NAT setup this will work without special forwarding or accepting of GRE packets (normally if you are not blocking outgoing connections and accepting established and related connections). The below two commands will get things going so PPTP and GRE work We first load the ip_nat_pptp module which allows PPTP to work with........
  • VboxManage VirtualBox NAT Network Issues Managment Troubleshooting


    If you find your NAT Network is not working properly, the first thing you may want to do is list the networks, check their status and make sure the Network is actually started and configured as you expect (eg. is DHCP on and enabled?). This is a long known, unresolved bug that seems to affect Version 6 randomly and disportionately on especially Mint 20/Ubuntu 18. https://www.virtualbox.org/ticket/1474........
  • Enable Turbo Mode for CPU Ubuntu Linux Mint Debian Redhat


    Sometimes due to your BIOS/EFI you may find that you have chosen "Energy Efficient" for your CPU which may effectively disable turbo mode. This is because "Energy Efficient" will often restrict or throttle your CPU to the base speed. This can impact nearly any CPU such as Intel's, AMDs, Opteron, Xeon etc... This is of course frustrating, for example if you have a CPU that is 2.0GHz base speed but turbo to 2.5GHz, you will never hit more than 2GHz.........
  • docker / kubernetes breaks Proxmox QEMU KVM Bridge VMs


    Docker adds iptables rules that break a lot of things including MASQUERADE or anything that needs the FORWARD table. If NAT is not working after Docker installation, it is probably because it set the iptables FORWARD policy to DROP. This may also make you think that your br0 or bridge is not working, but it's likely just due to what we'll mention later on below, that, Docker probably set your FORWARD chain to default DROP all packets, so nothing on your bridge ever makes it out........
  • Cisco UC CME How To Enable Licensed Features


    Router#show license Index 1 Feature: ipbasek9 Period left: Life time License Type: Permanent License State: Active, In Use License Count: Non-Counted Lic........
  • Linux Mint Ubuntu Ubiquity Installer Bug EFI Installed To Wrong Partition Solution


    Just an FYI that the installer ignores your selection of Boot Loader, as it was intended for MBR/Legacy. The installer horribly, even when choosing "Something Else" and manually partitioning and creating an EFIin your install drive, will still install grub to the first EFI partition it finds, even if you are following a guide like this to avoid wiping out the M........
  • amdgpu AMD GPU Xorg Won't Start [3576284.324] (EE) Segmentation fault at address 0x0 [3576284.325] (EE) Fatal server error: [3576284.325] (EE) Caught signal 11 (Segmentation fault). Server aborting


    Here is how Ifixed it on a Mint/Ubuntu install 1.) First download the latest AMDGPU-Pro driver from here: https://www.amd.com/en/support Navigate to your relevant video card: 2.) Download the installer One issue is that by default they give you a version for the latest version of........
  • Debian Ubuntu Mint DHCP dhclient quits and how to make it persistent if first attempt to get DHCP lease fails


    Debian based OS's have a similar issue as the behavior in RHEL/CentOS dhclient, which is that if you have an interface that relies on DHCP, if the first attempt fails, it will quit and stop. This is a problem especially if you are using your Linux as a router or something else mission critical, but where the internet for some reason may have been down or the DHCP server it gets a lease from broken. The expected behavior you would hope is that when things are back online that the........
  • 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........
  • 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........
  • 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........
  • Vbox Virtualbox DNS NAT Network Mode NOT working


    There is a random bug that sometimes occurs with Vbox NAT mode DNS, although it has never happened in the past and Vbox was working fine until recently. The symptom is that you can see it does get an IP+ DNS from the Vbox NAT DHCP. Below we use resolvectl dns and verify the DNS server is set to 10.0.2.3 which is the DNS from Vbox NAT. We can ping it but it does not respond to any DNS requests when we use dig @10.0.2.3 realtechtalk.com........
  • Docker Tutorial HowTo Install Docker, Use and Create Docker Container Images Clustering Swarm Mode Monitoring Service Hosting Provider


    The Best Docker Tutorial for Beginners We quickly explain the basic Docker concepts and show you how to do the most common tasks from starting your first container, to making custom images, a Docker Swarm Cluster Tutorial, docker compose and Docker buildfiles.........
  • Wazuh / OSSEC Install and Configuration Howto Tutorial Guide for Monitoring Agents SIEM


    How To Install Wazuh Server / Quickest Installation Wazuh (forked from the well known OSSEC project) is a full SIEM (Security Information Event Management) that works extremely well with the platforms it natively supports as an "Agent", which allows you to do scans of everything such as all processes running, CVE vulnerability check, incident reporting etc... Prerequisites: A lot of issues with Wazuh seem to be caused by i........
  • Linux Debian How To Enable Sudo/Sudoers for User "User not in sudoers file" Solution


    If you get an error that you aren't in the sudoers file, this typically means that your user is not designated as an admin with sudo privileges. In plain English, when it comes to some OS's like Debian including 10,11 etc.., by default the user is created without special privileges which is contrary to how Ubuntu/Mint handle the secondary user. Let's check the sudoers file to see the problem.........
  • iptables how to delete rules based on source or destination ip port or just the rule itself


    Let's say we have an IP that is dropped by iptables 192.168.20.2 service iptables status|grep 192.168.20.2 184 DROP all -- 192.168.20.2 0.0.0.0/0 You can use iptables itself like this to list the line numbers: iptables -L --line-numbers Two Ways To Delete The iptables Rule........
  • 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........
  • pulseaudio issue on QEMU/KVM guest VM when microphone is replugged/unplugged pulseaudio: pa_threaded_mainloop_lock failed pulseaudio: Reason: Invalid argument


    Here is the scenario, you are using QEMU/KVM and are using something like the AC97 sound driver to pass the host audio to the guest via pulseaudio. This is useful because you can transparently pass your mic input from the host which means you can mute your microphone from the host, which prevents the guest from receiving any mic input even if unmuted. Mute / Unmute Fix This issue also seems to happen even if you press the mute button on the microphone and then unmute,........
  • Virtualbox VBOX Howto Port Forward To Guests


    NAT Network, the VMs can communicate but your host cannot access them by default. NAT VMs have internet but cannot communicate with each other. Bridged is simple and allows full LAN access as if you had a physical machine plugged in but is often bad for testing, work or corporate environments and is not very portable when it comes to moving your VMs to other locations and networks. Here is how you can use NAT Ne........
  • Cisco Router Password Reset Howto Guide Solution Cannot Login /Unknown Enable Password 2600, 2800, 2900, 3900


    It is common that you may get access to undocumented equipment and need to reset the password. This applies to many Cisco routers whether 2600, 2900, 3900 etc... Cisco's Guide says to hit Ctrl +Pause/Break but if it doesn't work on some devices causing people to say "cisco password reset pause break does not work", you can see Cisco's alternative key combinations here:........
  • VirtualBox VBox Nat Network Handing Out Wrong IP Address Subnet Solution


    This seems to be an ongoing issue that is still reproducable in the latest Ubuntu Vbox 6.x. The default NAT Network range is usually 10.0.2.0/24. If you change this range it does not seem to work properly. Say we change the range to 10.50.1.0/24 If you get a new lease you will find that you get an IP from the old range but the default gateway is from the new range. ........
  • 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........
  • mencoder instead of ffmpeg to join or concatenate video files with different audio streams


    The problem for me is that Ihad two videos with different types of audio streams. ffmpeg would join them but they would not play past the point of the join. So Iused mencoder like below and it joined the audio and made them both mp3 streams and it worked! -oac mp3lame specifies the audio to be convered into an mp3 stream using the lame codec. after the oac the two files are the ones to be joined. the -o is the name of the outp........
  • 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........
  • Linux Mint Ubuntu Debian CentOS Dual Boot Install Issues


    The best way to avoid this problem is to understand how your BIOS is setup to boot. Often newer machines will default to U(EFI) which is different than the traditional MBR/Legacy mode. The problem is that this may not be apparent, often a BIOS Boot Menu will show a Legacy Boot Option and EFIOption without defining it. A good example of this is if your USB is called "Kingston" you may see in your Boot Menu "Kingston" and also "Ubuntu"........
  • apcupsd how to setup and monitor APC UPS units


    It really seems limited in that it can mainly give you the things you would see on the physical unit such as load etc.. wget https://downloads.sourceforge.net/project/apcupsd/apcupsd%20-%20Stable/3.14.14/apcupsd-3.14.14.tar.gz?r=https%3A%2F%2Fsourceforge.net%2Fprojects%2Fapcupsd%2Ffiles%2Flatest%2Fdownload&ts=1598115866 tar -zxvf apcupsd-3.14.14.tar.gz cd apcupsd-3.14.14 [root@somebox apcupsd-3.14.14]# ./conf........
  • Nvidia Ubuntu Linux Screentearing Video with solution driver


    This seems to happen on most if not all Nvidia cards but the good news is that if you are using any of the Linux drivers and have the nvidia-settings tool installed it is just a simple command. Solution: nvidia-settings --assign CurrentMetaMode="nvidia-auto-select +0+0 { ForceFullCompositionPipeline = On }" Enter the above command in your terminal and the screentearing will be fixed which is like enabling Tear Free on AMD cards.&........
  • CentOS 6 impossible to compile a newer libguestfs


    yum -y install gcc make gperf genisoimage flex bison ncurses ncurses-devel pcre-devel augeas-devel augeas readline-devel checking for cpio... cpio checking for gperf... no configure: error: gperf must be installed configure: error: Package requirements (augeas >= 1.2.0) were not met: Requested 'augeas >= 1.2.0' but version of augeas is 1.0.0 yum remove augeas augeas-libs augeas-devel wget http://downl........
  • 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........
  • QEMU-KVM KVM Command Line Practical Guide


    Iam going to build this based on a series of small howto QEMU / KVMposts I've made as I feel much of the information is actually hard to find and piece together from the rest of the web. What I'm going to focus on is how to use virtio as the NIC because if you don't you get very slow NIC speeds but with the virtio NIC model you basically get host speeds. /usr/libexec/qemu-kvm -enable-kvm -smp 8 -m 16000 -net user -net nic,model=virtio -drive file=ubuntu-gpt2l........
  • virt-resize: error: libguestfs error: could not create appliance through libvirt.


    This is caused because the user is running as qemu for virt-resize and if qemu does not have privileges to read from the source and write to the destination, it will fail with the below. So either change the uid of qemu or change the ownership of the source and target. Solution: export LIBGUESTFS_BACKEND=direct virt-resize --expand /dev/sda2 /root/kvmtemplates/windows2019-eval-template.img /root/kvmguests/kvmkvmuser4515........
  • Linux Mint Ubuntu Debian radeon slow 2D performance issues radeon_dp_aux_transfer_native: 158 callbacks suppressed


    radeon_dp_aux_transfer_native: 158 callbacks suppressed The simple answer is that radeon driver sucks and is a remnant of typical AMD/ATI issues. Use AMDGPUif you support it:........
  • How To Install python 3.4 3.5 and up on Linux with wine - Working Solution


    This is sure simple if you follow the guide but it took a lot of hacking around to make this work on Debian/Ubuntu! Now before you ask why bother running wine and python, the reason is because Python executables are NOT cross-platform. If you run pyinstaller in Linux, that binary will only run on Linux and the same if you do it in Windows. So it is preferable if you have a single environment that you can create Linux and Windows binaries from rather than running 2 separate........
  • MySQL 5.7 on Debian and Ubuntu - How To Reset Root Password


    MySQL on Debian versions is configured differently than the native local MySQL plugin so you will be disappointed when your password on the mysql client fails by default. Here is how you reset the MySQL root password the proper and "working way" #first we gracefully stop mysql sudo systemctl stop mysql; #then we forcefully kill any mysqld process just in case sudo killall -9 mysqld mysqld_safe;........
  • ssh how to connect using a SOCKS 5 proxy with nc and proxycommand


    This is not about using ssh as a proxy, but rather, using a proxy when you are SSHing to another host and using ProxyCommand (where we normally use nc as our proxy tool). In newer versions of nc the syntax has changed to the following: ssh -o ProxyCommand="nc -x 127.0.0.1:1234" %h %p user@host The format must be like above in newer nc versions. Just be sure to change the 1234 to the port of your SOC........
  • chown how to change ownership on a symlink


    If you just do a normal chown user.user somedir it won't work. You will see the ownership is still the previous owner. How To Change Ownership Of Symlink: The simplest part is just adding the -h which means no dereference so it applies the ownership on the symlink and does not try (and fail) to change ownership of the dereferenced symlink destination. chown -h user.user somedir........
  • mpv / mplayer with Radeon / AMD GPU Video Card Driver enable VDPAU GPU Accelerated Video Decoding


    The easiest way to know if your videos are playing with GPU acceleration are to watch the process of xplayer, mpv or whatever you are playing. The CPU usage should be no more than 10% for that process/program if it is using acceleration. Let's manually play with vdpau to make sure it works before we make it permanent: First make sure you have libvdpau installed: sudo apt install vdpau-driver-all If yo........
  • Debian Ubuntu Mint Howto Create Bridge (br0)


    Having a network bridge allows you to bridge traffic under multiple devices so they can talk natively without using any special routing, iptables/firewall or other trickery. To create your bridge you need the bridge-utils package for brctl and if you want to do things like bridge VMs that run on a tap device you will need the uml-utilities which provides "tunctl". 1.) Install the utilities to make our bridge sudo apt-get i........
  • Firefox Cannot Hit Enter Key In Address Bar and Location History Not Working


    Opening Firefox from the CLI reveals the following as the cause of the error: Query failed: Error: Error(s) encountered during statement execution: no such table: moz_favicons The symptoms of this issue are that in the address bar you cannot hit enter to browse to a site/url/address and your history cannot be accessed, nor does your history show up in the address bar when typing previously used addresses. This usually happens because you've........
  • Linux qemu-kvm How To Enable Soundcard in Guestl


    Pass QEMU this flag: -soundhw ac97 Or you could use (for a Ensoniq soundcard): -soundhw es1370 However on some machines I get this error: pulseaudio: pa_simple_new for capture failed pulseaudio: Reason: Connection terminated pulseaudio: pa_simple_new for capture failed pulseaudio: Reason: Connection terminated audio: Failed to create voice `ac9........
  • ssh reverse proxy to enable remote access behind a LAN and firewall


    So say you are behind a typical NAT/LAN setup whether at home, work or while travelling. What if you have a computer or server that you need to connect to from the outside? Yes you could use a VPN but a quick and dirty, temporary and secure way is to use SSH's Reverse Tunneling Proxy feature. Requirements On the remote ssh server host you need the GatewayPorts option enabled in sshd_config (be........
  • How To Use Letsencrypt SSL/TLS Encryption to Create Certificates without installing on the target machine


    For some reason, perhaps you don't want to run a daemon or let Letsencrypt have access to your production server. There is a way to use it like a normal CSR/CA setup in manual mode. ./letsencrypt-auto certonly --manual -d realtechtalk.com - www.realtechtalk.com   Eventually you will get prompted to create a certain path and file with certain data: Create a file containing just this data: Casdfasfadsfsad........
  • iptables linux firewall recommended rules for public computing


    Whether you are at work, at the coffee shop or on the public internet here are some basic but effective rules for iptables that lock things down (eg. no one can SMB or SSH to you or really anything): # Generated by iptables-save v1.4.21 on Fri Dec 14 14:00:08 2018 *nat :PREROUTING ACCEPT [160:19844] :INPUT ACCEPT [4:357] :OUTPUT ACCEPT [2955:182236] :POSTROUTING ACCEPT [2955:182236] COMMIT # Completed on Fri Dec 14........
  • VMWare Pro Workstation Nic Disconnected and No IP Using NAT


    By default VMWare Workstation often doesn't work as we would like. If you create a VM with a default NAT IP it won't work you will find the NIC is disconnected (even though on the VMWare side it says connected including at Power On). How To Solve It 1.) Create New VMNet for NAT Click "Edit" -> "Virtual Network Editor" Click "Add Network" Select Network To Add "VMNet1" (........
  • Proxmox Breaks Storage/LVM Backing If Killing QEMU-IMG


    I tried to stop a qemu-img copy or clone and it broke everything. It was fine to "stop" it from the GUI but a process still persisted so I killed the relevant qemu-img and the kernel went crazy. It also may not have helped that I tried to lvremove a different volume (an unused disk). But either way it breaks LVM (you cannot even run lvdisplay) so a reboot is necessary. Jan 17 06:45:21 testserver kernel: [ 5680.439337] systemd-udevd D 0&nbs........
  • Linux partprobe/partx cannot access last and 4th partition


    On a test machine Iwas never able to access to a newly created 4th partiton. As we can see there are dev devices for everything but the 4th partition. The normal "partprobe" or "kpartx" or kernel being told to rescan the block device didn't help (only a reboot did). fdisk -l /dev/sda Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders Units........
  • Bash How To Cut or Split Natively And Get The LAST Field


    This takes "yourvariable" and splits it based on the last character in this case "-" and shows the last field of that split. ${yourvariable##*-} ........
  • Bash Script How To Manipulate Text/Strings By Searchig and Replacing Natively


    # a single first slash means first occurrence # format=${haystack/needle/replacement} # if you use a double first slash it means ALL occurrences # format=${haystack//needle/replacement} email=${file/.txt-marked/} In the example above we are searching in the variable $file for ".txt-marked" and replacing with nothing (the empty part after the last / means we are replacing with n........
  • How Does Cisco CUCM (Cisco Unified Communication Manager) Work?


    Cisco's CUCM (Cisco Unified Communication Manager) is a system that combines voice, video, data and mobile products into a single unified management suite. At its core, the CUCMis like a "Super PBX" that controls the flow of all communications through an organization even single or multiple site deployments. Cisco's CUCMmakes communication more effective and simple through centralized management and unification of communications resources.........
  • systemd management using systemctl and journalctl to check systemd logs


    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands: list-units [PATTERN...] List loaded units &nbs........
  • vi error solution E166: Can't open linked file for writing


    This is not so much of a vi error as it is a physical filesystem error in the sense that the file you are trying to write to is a symlink and the destination doesn't exist or for some other reason is inacessible. So vi is tellng you "you're writing to a symlinked file and the file the symlink points to cannot be written to". This is especially highlighted byt he fact that if you are using wq! to write and you still get the error.........
  • VMWare Vsphere VCSA Graphical Install Creates json


    yes it does create its own json ============================================ cat /tmp/vcsaUiInstaller/ovftool-20180809-175238948-20180809-175603497.log |grep -i json 2018-08-09T17:56:04.238-07:00 verbose OVFTool[30966] [Originator@6876 sub=Default] Manifest file entry: SHA1(VMware-vCenter-Server-Appliance-6.7.0.12000-8832884_OVF10-file1.json) = 1deb658c724767697587d5909c4051c01813e6a1 --> ........
  • Debian Mint Ubuntu compiling xmr-stak


    sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3 sudo apt-get install libcurl4-gnutls-dev git clone https://github.com/wolf9466/cpuminer-multi sudo apt-get install cmake libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev git clone https://github.com/fireice-uk/xmr-stak-cpu.git make install cd bin chmod +x xmr-stak-cpu ./xmr-stak -O xmr........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • OpenVPN cannot ping remote IP routing loop issue after connecting


    Sometimes if you have a very basic configuration OpenVPN on the client side for some reason sends all traffic to the OpenVPN server IP through the tun0 which is of course impossible and creates a block or routing loop. This is because you need to use your normal ISP/LANgateway to hit the OpenVPN server if it is remote/offsite as is usually the case. So if you are connected to the OpenVPN through say a tun0 device and your routing is set to connect to the OpenVPN&nbs........
  • Linux Mint Black Screen after boot no graphics solution


    This is not the normal "black screen"issue and I was shocked to eventually find out why. The normal advice of reconfiguring Xorg didn't work. Even booting into "Recovery Mode" did not help. Here is the short end of the stick that fixed it: sudo apt-get install mdm mate-desktop-environment Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled. This must be whe........
  • Linux Mint Ubuntu Debian How To Disable Webcam Automatically Onboot To Prevent Spying and Privacy Violations


    It is well known hackers, the NSA, CIA and other groups have created malware to secretly turn on your webcam and microphone on your phone, tv etc.. But fortunately on our computers and laptops we have some options. Most webcams use the "uvcvideo" kernel module / driver. You can disable this in two ways on boot. I recommend both just as a failsafe. Disable it on rc.local once your system boots automatically Add the followi........
  • Apache htaccess Custom ErrorDocument not working properly for root home page 403 Error Issue and Solution


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  • Linux How To Clone One System Harddrive to another remote system


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    One of the purposes of rsync is to backup whole filesystems and archive them but how can you do that properly and restore things to normal if all permissions and ownerships are not preserved from your root filesystem? It's not desirable to have everything running as root, especially not just for an rsync. The Easy rsync preserve permission solution for non-root users sudo is the answer and all you have to do is edit /etc/sudoers At the end o........
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    I wanted to Import/Use a .vmdk hard disk image file from VMWare. Generally you can just "point" VirtualBox to it and use it and it will work but I found an exception. One of my Centos 4.4 x64 images wouldn't boot. I had two copies, an older one and the newer one. The older one booted as normal (once I changed the VirtualBox driver to IDE from SATA). The newer one stopped at the "GRUB loading" message no matter what I tried. As far as........
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  • How to chroot properly into your OS/distro


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  • Linux How To Add/Delete A Default Route/Gateway


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  • DRBD WFConnection Problem/Solution


    This has stumped me a few times because I keep forgetting that Centos 5.5 comes with a default iptables configuration that ends up blocking DRBD traffic,I tried all the normal things and couldn't understand why I couldn't make my normal DRBD config work. So if you have WFConnection problems and have tried the normal "mailing list" fixes, check your firewall status first! Both Nodes Say the Following: version: 8.3.8 (api:88/prot........
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    This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned. I didn't blame Seagate for their past issues until now. This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family: Seagate Barracuda 7200.11 Device........
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    It's basically free bash shell script available from: http://wpkg.org/email2fax/index.php/Main_Page Make sure you have the required tools: libtiff ghostscript mpack/munpack Where you can e-mail your Asterisk box and it will fax it to the phone number in the subject line. The good news ends there, it is fairly undocumented and buggy. Take for example how the documentation mentions you can invoke from the com........
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    The folder I was trying to archive is about 72GB, but much like rsync at about 17GB it chokes because of the filesize. What's with so many common and essential Linux tools having such limitations? I guess it is likely that the authors never wrote their code with the idea that files would be so large but it's still very annoying. It's important to stay on top of these limitations on production servers because I didn't realize what happened until I checked the file with "........
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    All you have to do is browse to: C:Documents & SettingsYourUserName and you'll see the following: Inside "My Recent Documents" are of course shortcuts to the most recent documents you opened Inside "SendTo" is your sendto, you could edit that to Send a file to a network destination, your Flash Drive........
  • Compaq V2405CA Laptop - Unixbench Performance Test


    Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics. # # # # # # # ##### ###### # # #### # # # # ## # # # #&nb........
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    Clone any OS partition perfectlyIn one box I needed to copy the boot partition to another disk while retaining the MBR and other data. I simply ran this command: [code:1:1b1ff110ca]dd if=/dev/hda1 of=/dev/hdb1[/code:1:1b1ff110ca] [b:1b1ff110ca]if[/b:1b1ff110ca] = source patition [b:1b1ff110ca]of[/b:1b1ff110ca] = destination partition Here's an interesting article on it http://www.rajeevnet.com/hacks_hints/os_cl........
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    /usr/bin/ld: cannot open crt1.o: No such file or directory[quote:812bec9db7]/usr/bin/ld: cannot open crt1.o: No such file or directory collect2: ld returned 1 exit status[/quote:812bec9db7] This is annoying and in my case it happened on Centos AMD 64 when compiling a 32bit program with GCC. Install glibc-devel.i386 (make sure you get the i386 version and not the native 64 bit version which is likely already installed). The joys of 3........
  • Intel's Finnish Fetish


    Intel's Finnish FetishIntel's Finnish Fetish By Dave Mock June 13, 2005 Chipmaker Intel (NASDAQ: INTC) has successfully topped the personal computer market for decades. Breaking into related areas such as communications has been much difficult for the world's largest semiconductor maker. But a new partnership with Nokia (NYSE: NOK) could help to change that. Intel's forays into cellular-phone and home-entertaiment-device chips have........
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    CDR Manufacturers - Why is so much media bad?I have searched for good media and tried many kinds for years. I guess I'll try to summarize my findings and conclusions. Dye is irrelevant, dye of any color can be good or bad, it more likely depends on the manufacturer. Speaking of manufacturers, the name at the top of the disc means nothing. For example, Memorex along with any other 'brand' is actually always made by another manufaturer including CMC Mag........
  • African money SCAM


    African money SCAMI have received countless of these sorts of emails where the person claims to be from an African nation which has a deposed finance minister or some other strange situation which puts millions of dollars at their disposal. The only problem is that they need a partner to get the money out. And they have entrusted only you, yes that's right, to donate your bank account information along with SIN number so they can secretly wire the money over and you w........
  • Basic Port Listing


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  • pound a Linux Load Balance and Reverse Proxy


    I have played around with Pound a little bit. It is a reverse proxy and load balancer in one, and it can be used as only a reverse proxy if you like. It is very simple to configure as either, and Pound even senses if one of the systems is down and stops sending requests to the dead server. It supports SSL (but passes the request to the destination server unencrypted) and even the Apache log format. Pound is very simple, fast a........
  • Adventures in pre-paid SIM Cards and data GPRS/Edge/3G in China with China Mobile in Shenzhen, Guangzhou, Shanghai, Beijing and other cities


    This really is a difficult and confusing process for non-Mandarin speakers, but here's what I've done and learned so far: You can purchase an "M-Zone" China Mobile pre-paid SIMCard from almost anywhere but I tried to purchase mine from Suning (a large electronics dealer) hoping they would be able to help me or answer my questions but my plan didn't work out at all. At Suning once I found someone who spoke some English they gave me the 55 RMB M-Zone China Mobile P........
  • How to avoid web content hijacking/copying/Force content to be accessed by only 1 domain name


    This is something that happens a lot and it is very dirty, as you probably know each site is hosted on a certain IP address. Sometimes a domain is hosted by a single IP address and the IP address defaults to this very same domain. This means that if someone buys domain abcd.com and enters your IP address (the one of your website) as the A record, your content will show up on their domain as if it was their own. There is an easy way to prevent this by using .htacces........
  • The power of passive vs air cooling. Small fans make a world of difference.


    I bought a Dynatron A46G for my AMD X4 620 AM3 Quad Core CPU. Just judging by touch, the stock OEM fan/heatsink combo kept things so cool, I could leave the 1U server on the floor and it barely felt warm to the touch, including the heatsink itself. I thought the Dynatron A46G would be enough with passive cooling (it has no fan), but the same setup became burning hot on the underside of the server and also by touching the heatsink itself within minutes. I thought that th........
  • Unixbench Score with Glusterfs/Openvz & Quad Core Xeon - Updated with GlusterFS 2.0.8 & Optimized Client Config


    The results are still not flattering and are nothing close to native performance. Unless GlusterFS has a "DRBD-like" option to delay writes over the network and to only read from the client side, I don't see how performance can ever improve much more. After doing some client optimizations Iadded more to the score: Start Benchmark Run: Sun Nov 29 00:37:44 PST 2009 00:37:44 up 3 min, 1 user, load average: 0.01........
  • 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........
  • 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.........
  • How To Save iptables firewall rules Centos/Redhat/Fedora Linux


    This is something that annoys a lot of people, fortunately the Redhat style OS's are the most simple in this respect. I disagree that Debian's way makes sense, it is more of a hackish approach in how they implement iptables. Anyway, for those who are using Redhat/Centos style OS's it is very simple. Set your rules from the shell/command prompt and to save the iptables firewall rules so they are remember/loaded on boot just run this command: service iptables........
  • iPhone Backgrounder Adds True and Real iPhone multitasking on jailbroken phones


    Apple crippled the iPhone by not allowing multi-tasking of the non-primary apps. I use SSH a lot and I don't want to close my session just to check my e-mail, etc, now an app found in Cydia called "Backgrounder" allows just that. Although it's not perfect, we installed the correct one for "3.x" iPhones and hit "Reload SpringBoard" and the hour/circle glass has just been going for minutes. It seems like it installed fine even with the crash t........
  • SSH Server Slow/Lagged/Delayed Login Response


    This is really something the SSHServer developers should consider. The cause of this annoyance is because of failed DNS lookups on your IPaddress, which is especially common for many dedicated/col-located servers and also computers on internal NAT/private networks. The chances are this is the cause of your SSHSlow/Delayed Login problems. The easy solution to SSH Login Problems Edit /etc/ssh/sshd_config Add this line to disable r........
  • 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........
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