• 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". Install the utilities to make our bridge sudo apt-get install........
  • 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


    So I have a domain "testdomain.com". Inside test domain.com's root is the following .htaccess: Options +FollowSymLinks -Indexes ErrorDocument 403 /launch/index.html Order Deny,Allow Deny From All Allow From 192.168.1.2 When you visit anything other than root things work fine. Eg. if you visit http://testdomain.com/somedirfile.html It will show the right error in /launch/........
  • Linux How To Clone One System Harddrive to another remote system


    The easiest way is to use SSHand DD or a combination of netcat. SSHwill be a little slower due to encryption but is the most secure way (on two older systems the average clone speed is about 40-50MB/s). This is also OS independent as it doesn't matter what the source OS is because you are literallly cloning the drive so you retain the partition table and settings. Clone HDD using SSH and DD........
  • W: GPG error: http://archive.debian.org squeeze Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY AED4B06F473041FA NO_PUBKEY 64481591B98321F9


    W: GPG error: http://archive.debian.org squeeze Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY AED4B06F473041FA NO_PUBKEY 64481591B98321F9 No clue how to fix this.........
  • h264 DVR security camera footage cannot be played


    This is not just a Linux issue but a general issue most software or hardware players cannot play the resulting exported/backed up format of .h264 from DVR security camera footage for some silly reason. There is a simple solution in Linux using ffmpeg fortunately. Convert the .h264 file into mp4 ffmpeg -i yourfile.h264 -codec copy video.mp4 play dvr .h264 file........
  • yum how to install old obsolete packages


    This is important as unfortunately Centos may designate a package obsolete and the replacement breaks everything (eg. you have a config file and the new replacement is not at all compatible with it and it breaks your application). This is where disabling obsoletes comes into play, it can be done from yum but it doesn't work at the time I find. yum --setopt=obsoletes=0 install someapp However Ifind it still installs the new app and not the one you ask for........
  • iptables v1.4.7: can't initialize iptables table `NAT': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded.


    iptables -t NAT -A PREROUTING -s 24.30.44.0/24 -j DNAT --to-destination 10.10.10.1 iptables v1.4.7: can't initialize iptables table `NAT': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. Solution # it is case sensitive "nat" and DO NOT use "NAT" or you will get this error! iptables -t nat -A PREROUTING -s 24.30.44.0/24 -j DNAT --to-destination 10.10.10.1........
  • rsync specify alternate port non-standard port than 22


    It is not obvious but the rsync --help rsync --help|grep port --port=PORT specify double-colon alternate port number --port does not do anything at all actually for some strange reason it still uses 22 You have to specify a manual ssh command to make it work: -e 'ssh -........
  • ffmpeg how to watermark and concatenate in one command


    If you were in my boat you were frustrated that you had to double encode, eg. one separate encode for watermark and a separate from concat and it's not easy to figure out this with ffmpeg on your own. However it is a nice way to save time! ffmpeg -i file1.mp4 -i file2.mp4 -i file3.mp4 -i watermark.png -filter_complex "[0:v]setpts=PTS-STARTPTS[v0]; [1:v]setpts=PTS-STARTPTS[v1]; [2:v]setpts=PTS-STARTPTS[v2]; [v0][0:a][v1][1:a][v2][2:a]concat=n=3:v=1:a=1[v][aout]; [v][3:........
  • ffmpeg trouble concatenating similar but different files


    When things go wrong your video is basically unplayable or the first video plays fine and then freezes when moving on to the next. Generally if both videos weren't produced with the exact 100% same settings you will have issues. You can try the basic concat but it often won't work right. Solution for me: My example uses 3 videos in total so "n=3" and a=1 to include audio. ffmpeg -threads 12 -i file1.mp4 -........
  • Linux Mint USB Kernel Tainted and Locked Port/Dev File


    Essentially a program I was running for mining did not terminate properly with Ctrl+C it is listed as defunct and cannot be killed, kernel is tainted and normal tricks to disable the port are impossible the dev and sys entries for the device cannot be browsed or interacted with in any form without a lockup of the request. The only solution is to reboot due to the kernel taint as far as I can find so far. [1130246.811056] INFO: task minerd:21861 blocked for more th........
  • Linux how to copy GPT partition table with dd


    The old MBR 512 bytes partition table is no longer valid if you are using GPT. To copy a GPT table with dd to another disk do it like so: Below sda is the source disk and destination disk is sdb (change to meet your needs). dd if=/dev/sda of=/dev/sdb bs=1536 count=1 You can also use dd to backup your partition table like normal but with the bs of 1536 dd........
  • Reading package lists... Done W: GPG error: http://ppa.launchpad.net trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D46F45428842CE5E


    Still looking for the solution Working Solution 2017/07 sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys D46F45428842CE5E Solution gpg --keyserver hkp://subkeys.pgp.net --recv-keys D46F45428842CE5E gpg: requesting key 8842CE5E from hkp server subkeys.pgp.net gpg: keyserver timed out gpg: keyserver........
  • phpBB3 slow and internal dummy connection


    Using Apache 2.2 and PHP5.6 PHPBB3 is very slow to respond. Actually for some reason it takes so long to even register a log entry in access_log as in several seconds or a few minutes later it shows up in Apache. All other vhosts and Apache access stops working and freezes until the request to access PHPBB3 slowly completes. It seems to randomly be slow if you stop using it whether for posting or reading the forums. I've migrated to different machines including........
  • ssh forward multiple ports in the same connection and command even works with NAT!


    You can actually just pass multiple "-L" statements to achieve this. An example is as below: ssl -L 80:192.168.10.5:80 -L443:192.168.10.5:443 -L2068:192.168.10.5:2068 -L 8192:192.168.10.5:8192 user@remotehost.com The above essentially is saying forward ports 80,443,2068,8192 to the remote IPof 192.168.10.5 (even though it is behind NAT). Essentially SSH will do the NAT part even if the........
  • Avocent DSR8020 KVM/IP - Network Connect Error - Solution


    This error is commonly due to Java security or TLS settings but there is a second issue with forwarded ports that also causes it. 1. Java Security/TLS Settings issue: This article has the solution to change them all in Linux automatically 2. Port Forwarding Issue if your Avocent DSR is behind NAT/private IP........
  • Unable to mount location Failed to retrieve share list from server: No such file or directory solution


    Cannot even "Browse Network" when clicking on "Windows Network" Unable to mount location Failed to retrieve share list from server: No such file or directory logs: [2017/02/14 00:16:44.271314, 0] ../source3/nmbd/nmbd.c:58(terminate) Got SIGTERM: going down... [2017/02/13 17:35:41.797944, 0] ../lib/util/become_daemon.c:124(daemon_ready) &........
  • DRBD Split-brain solution


    Uh oh [17925926.174277] block drbd0: Handshake successful: Agreed network protocol version 96 [17925926.174325] block drbd0: conn( WFConnection -> WFReportParams ) [17925926.174342] block drbd0: Starting asender thread (from drbd0_receiver [1682]) [17925926.174432] block drbd0: data-integrity-alg: [17925926.174581] block drbd0: drbd_sync_handshake: [17925926.174586] block drbd0: self 2AAE66AF9252D6DB:2815BF........
  • How to clear all iptables rules for all tables and chains


    iptables -F iptables -t nat -F iptables -t mangle -F This is as simple as it gets.........
  • iptables how to forward localhost port to remote public IP


    iptables -t nat -A OUTPUT -m addrtype --src-type LOCAL --dst-type LOCAL -p tcp --dport 3306 -j DNAT --to-destination ip.ip.ip.ip iptables -t nat -A POSTROUTING -m addrtype --src-type LOCAL --dst-type UNICAST -j MASQUERADE sysctl -w net.ipv4.conf.all.route_localnet=1 Make sure you substitute "ip.ip.ip.ip" for your real public IP and also the "--dport 3306" for the port you want to forward. Finally run the sysctl command and........
  • Linux How To Recover Partition Table from Kernel and Restore Centos/Debian etc..


    We've all done this at some point, you work on the wrong shell window and this was my first time making this mistake but I deleted a partition table in fdisk, recreated it and saved it with "wq" and even ran partprobe! If you haven't rebooted yet then you can still recover your partition table, otherwise you're in big trouble. Fortunately since it was a live system and in use the kernel still had to use the old table like below:........
  • OpenVZ Error: Failed to load 2nd level quota solution


    Syncing private Live migrating container... Syncing 2nd level quota 11000: invalid option -- F Usage: vzdqload quotaid [-c file] commands Loads user/group qouta information from stdin into quota file. -c file use given quota file Commands specify what user/group information to load: -G grace time -U disk limits........
  • 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........
  • 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.........
  • A start job is running for /etc/rc.local Compatibility


    According to this and my own experience it is the case that you have started something running in the foreground or a server that does not terminate with a normal rc.d script. The server will reboot once you kill whatever command or process that is.........
  • 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........
  • Linux Mint Network Manager Connection Disconnect Option Grayed Out


    This is a real pain because I had to manually unplug ethernet cables for network testing or to use an alternate network or guarantee physical access to one network segment is cut off. For some reason this happened after Ikilled dbus because it was confused and blocking packets thinking they were coming from the wrong interface since eth0 and eth1 both had the same subnet and gateway. I eventually did a "service network-manager restart" but the option was........
  • Avocent 8020 KVM Java Icedtea Viewer


    It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post. *If you get the icedteaweb window but nothing loads or prompts it is probably your security settings that won't even prompt to run it. See this article to solve that problem. To fix this error you need to edit the java.security file m........
  • tsclient (Terminal Server RDP Client) missing in Debian, Ubuntu, Linux Mint


    This was a horrible shock after upgrading fromUbuntu 9 to Linux Mint 17 and I found that the last distro to support tsclient was Debian Squeeze. For some reason it has disappeared for a long time and the new options such as rdesktop and gnome-rdp do not have any start menu entry and just aren't done as well as tsclient. Fortunately there is a solution: tsclient surprisingly can be downloaded as a direct .deb package and it fails with some variou........
  • 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........
  • initial Main Mode message received on 192.168.5.94:500 but no connection has been authorized with policy=PSK


    If you are getting this error from Pluto/IPSEC it is almost always due to a routing or NAT issue.........
  • Firefox errors Unable to generate public/private key pair. (Error code: sec_error_keygen_fail)


    Your firefox is out of date if you get errors like below: Secure Connection Failed ........
  • Avocent Unable to load resource avctVideo.jar


    Avocent Unable to load resource avctVideo.jar Avocent requires port 80 and 443 to be forwarded or you will get a message like above if it's on a NAT network and you are accessing it from the outside (internet).........
  • iptables port forwarding multiple ports to another IP


    iptables -t nat -A PREROUTING -p tcp -m multiport --dports 80,443,2068,8192 -j DNAT --to-destination 192.168.1.175 Just adjust the "--dports" to the ports you need and the --to-destination to the destination IP (note it must be on the same network as the server running iptables........
  • HP XW9400 Motherboard In Desktop Issues


    Fortunately the format is EATX so an EATX case will work and the screw layout is standard. You will need to remove the HEX/TORX screws that are connecting the stock HP standoffs (meant to slide into an HP case). XW9400 Motherboard Issues Size: 12" x 13" Proprietary Power Connector Proprietary CPU Power Connector Proprietary Memory Power Connector Fan connectors are 4 pin so you will need some kind of adapter.........
  • The redirect URI in the request: urn:ietf:wg:oauth:2.0:oob can only be used by a Client ID for native application. It is not allowed for the 'WEB' client type.


    You need to set your application type as "Desktop" even though this would sound counterintuitive.........
  • 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 managing virtual machine images


    libguestfs tools howto guide for managing virtual machine images 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 To list partition info on the image: virt-df image.img Filesystem........
  • NS_ERROR_FAILURE (0x80004005) The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.


    The solution is to run '/etc/init.d/vboxdrv setup' and sometimes happens when upgrading VBox and the kernel modules don't get upgraded with it. Sometimes the above doesn't work until you reboot because sometimes other unknown processes (even the file manager possibly) may be locking the old module from being unloaded. Failed to open a session for the virtual machine XP. The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.........
  • Openvz iptables v1.4.7: can't initialize iptables table `nat': Table does not exist (do you need to insmod?) Perhaps iptables or your kernel needs to be upgraded. solution


    iptables -t nat -A PREROUTING -p tcp -m tcp -d 192.168.2.1/32 --dport 3389 -j DNAT --to-destination 192.168.5.2:3389 iptables v1.4.7: 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 above is often because you don't have the correct modules loaded on the hostnode or enabled for the container but in some cases it's actually a weird openvz setting. Che........
  • Postfix how to secure outgoing authenticated e-mails for privacy and hide the IP address, mailer and other things


    The most common solution is to use the /etc/postfix/header_checks but this is a big problem. Why is header_checks a problem? Because it does it to all mail whether incoming or outgoing and whether authenticated or not. We of course want as much header information for incoming as we can get for many reasons but many organizations want to secure and make their mail clients as secure as possible. I adapted this solution to the client's custom config, they are configur........
  • iptables how to forward port to another IP address with DNAT


    -A PREROUTING -d 98.98.98.5/32 -p tcp -m tcp --dport 1050 -j DNAT --to-destination 192.168.1.50:3389 The above forwards port 1050 on IP98.98.98.5 to 192.168.1.50 port 3389 (you can obviously edit things to meet your needs).........
  • drbd 8.3 hard drive failure recovery example


    drbd 8.3 hard drive failure recovery drbdadm attach r0 DRBD module version: 8.3.10 userland version: 8.3.8 you should upgrade your drbd tools! 0: Failure: (119) No valid meta-data signature found. ==> Use 'drbdadm create-md res' to initialize meta-data area. ........
  • drbd won't create device if previous partition is on it Command 'drbdmeta 0 v08 /dev/md160 internal create-md' terminated with exit code 40


    This is what fixed it: [root@box13 ~]# dd if=/dev/zero of=/dev/md160 bs=512 count=500 Basically you need to wipe out more than just the 512 byte partition table so 512 bytes * 500 is more than enough to make DRBD happy and think the partition is now empty. The reason this happens is because it gets confused when there is a previous partition with data on the device you are using. root@box13 ~]# d........
  • 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........
  • iptables howto multiport forward in single line example


    -A PREROUTING -p tcp -m multiport --dports 10000,18080,13306 -j DNAT --to-destination 192.168.5.83........
  • Delete all comments from wordpress (in case of extreme SPAM)


    *Note this will delete all comments indiscriminately. DELETE FROM `wp_comments` To delete all but save specific comments based on "author e-mail use the following". Add more e-mails below in the same format if you have more. DELETE FROM `wp_comments` WHERE NOT comment_author_email IN ('user@hotmail.com','another@hotmail.com')........
  • Sipura / Linksys PAP/VOIP/SIP Adapter Issue Can't receiving incoming phone calls and you're behind a NAT router (99% of people)? solution


    Sipura / Linksys PAP/VOIP/SIP Adapter Issue Can't receiving incoming phone calls and you're behind a NAT router (99% of people)? 1. Login to the adapter. 2. Click on "Advanced" (location varies but usually somewhere on top) 2. Click on "SIP" 3. Scroll down to "NAT" (usually at the bottom). You'll find 2 columns with 4 rows of drop-down boxes (they'........
  • Dell FS12-NV7 2U Server Information and Guide


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