hostapd how to enable and use WPS to connect wireless devices like printers

Edit your /etc/hostapd/hostapd.conf file like below and restart hostapd. #WPS stuff # Enable control interface for PBC/PIN entry ctrl_interface=/var/run/hostapd eap_server=1 wps_state=2 ap_setup_locked=1 wps_pin_requests=/var/run/hostapd.pin-req config_methods=label display push_button keypad #WPS model info stuff change to suit your needs device_name=USB2.0 WLAN manufacturer=ATHEROS model_name=WAP........

zfs and LUKS how to recover in Linux

Sometimes users take their removal drives and unplug and replug them to test what happens during the failure of a disk. However, this breaks things quite badly due to the /dev/mapper in LUKS not coming back online due to it not being closed. In other words, generally with non-encrypted drives the process is smooth but when encrypted you may want to follow a strategy like this: We can see below that both disks are unavailable as they were physically remov........

How to use the FTDI USB serial cable to RJ45 adapter to connect to the console on Cisco/Juniper Switch Router Firewall in Linux Ubuntu Debian Redhat

This should work for most console ports of other manufacturers too. It is a quick and simple method for emegencies or deploying a few appliances/devices in a non-standard environment or small environment. However, if this is a route thing, or the equipment is not physically close to you, it would be best to use some sort of "Terminal" server which is an IP connected switch with several serial ports built-in for this purpose. Normally they accessible by web/........

kernel panic initramfs not syncing cause solution

Check your initramfs if it's missing /dev/null or /dev/console, this is likely the reason. If you want all actual devices to be created you could also enable devtmpfs in your kernel (.config) and mount like this during init: CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y mount -t devtmpfs none /dev But note devtmpfs will not create /dev/null or /dev/console for........

RHEL 8 CentOS 8, Alma Linux 8, Rocky Linux 8 System Not Booting with RAID or on other servers/computers Solution for dracut and initramfs missing kernel modules

This seems to have changed for RHEL 8 where a normal dracut to update your initramfs creates a system that only boots for the running kernel. For example if you have Kernel 5 and then chroot into a RHEL 8 variant which uses kernel 4.18, and run dracut, it seems that by default the system will be unbootable. It is also the case that if you move your RAID array or drives to another server that it will be unbootable, because dracut seems to only include modules needed for the curre........

Grandstream Phone Vulnerability Security Issue Remote Backdoor Connection to 207.246.119.209:3478

Have you checked your router/firewall logs and disconcertingly see connections to an unknown IP207.246.119.209:3478 from your Grandstream VOIPphones? You're not alone and the Grandstream forums have discussed this issue. However, even their own staff d........

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.........

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........

Cisco Switch / Router How To Restore Factory Default Settings

1.) Make sure your conf register is 0x2102 Do show version and at the very end of the output you will see the Configuration register. show version Configuration register is 0x2102 If the config register is not 0x2102 then enter this command: r1#configure terminal r1(config)#config-register 0x2102 r1(config)#end 2.) Let's Erase the NVRAM/flash........

Error opening tftp://10.0.2.2/network-confg (Permission denied) - How To Fix Cisco Router Switch Error Solution Console

How To Fix This Cisco Switch/Router Error %Error opening tftp %Error opening tftp://10.0.2.2/network-confg (Permission denied) %Error opening tftp://10.0.2.2/cisconet.cfg (Permission denied) %Error opening tftp://10.0.2.2/router-confg (Permission denied) %Error opening tftp://10.0.2.2/ciscortr.cfg (Permission denied) %Error opening tftp://10.0.2.2/network-confg (Perm........

Debian Mint Ubuntu Howto Disable Network Manager

NetworkManager is normally good for GUI users who may not be good with manually confguring devices, but if you are using things like bridging and bonding, it will often break things. How To Disable NetworkManager systemctl disable NetworkManager Now that it's disabled you will need to stop NetworkManager. NetworkManager will still be running until you reboot next or manually stop it. How To Stop NetworkManager systemctl stop........

/var/log/journal huge/too large solution in Debian Mint Ubuntu Linux Howot Fix

Is your /var/log/journal overweight and bloated? For example a decent install of Debian 11 with most applications and services ends up being about 4.9G with the journal taking a few gigs. du -hs /var/log/journal/ 1.3G /var/log/journal/ By default in a lot of distributions there is no maximum size so it will keep growing. This is especially problematic for embedded distributions and devices, but is also a huge waste of sp........

RTL8821AU Setup Configure Wifi Realtek 8821 in Linux Debian Mint Ubuntu Howto

The easiest way for the 8821AU Realtek Wifi chipset / TP-Link T2U Plus: Bus 002 Device 003: ID 2357:0120 TP-Link Archer T2U PLUS [RTL8821AU] First install your kernel headers/source/other required tools: sudo apt install linux-headers-`uname -r` make gcc bc Clone this github repo with the driver: git clone https://github.com/morrownr/8821au-20210708 Run the compile/ins........

Linux Debian Mint Ubuntu How To Add Non-Free Repositories and Contrib

You just add on "non-free" at the end of each repo, like the example below: If you wanted contributed packages then you could also add "non-free contrib" to each repo line. Don't forget to do an "apt update" to see the new packages, this is especially handy for getting more drivers for devices with the firmware-linux-nonfr........

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........

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.........

Zoom Password Error 'That passcode was incorrect' - Solution Wrong Passcode Wrong Meeting Name

Have you been given a Zoom password that the meeting owner says is correct but it doesn't work anymore or never works? If the meeting name says "Zoom Meeting" and it's not really named that (which most meetings are not), then the issue is usually that there is an initial password to be able to join, aside from the passcode. It basically means that Zoom has deauthenticated you randomly or maybe after X amount of uses, without clicking on the Join Meeting URL which contains a........

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........

Cisco Howto Configure Console Port/Terminal/Comm Server with Async Cable Setup

This assumes that you've already installed the relevant HWIC cards eg. Cisco Asynchronous Serial NIM These are essentially cards that you install into your router, once installed you connect an Async cable to one of the ports on the card which normally gives you 8 console cables and are normally labelled 1 through 8. You connect all of the cables to the devices you need (even non-Cisco devices) whether switches, routers or firewalls, they will usually work. The real m........

SSH cannot connect to old servers/devices/switches/routers/Cisco/Juniper Unable to negotiate with 192.168.20.2 port 22: no matching key exchange method found. Their offer: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hell

A lot of older devices either support telnet or very old SSH keyx algorithms which are insecure and disabled by all newer/modern SSH clients for security reasons. However, sometimes you may be on a LAN via VPNor some other secured network or for whatever reason, absolutely, need to connect to this device and sometimes old/embedded devices may not be possible to update to a newer SSH server. If you run into this you may be using a modern/newer SSH client and get thi........

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:........

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........

Scanner not working in Linux Ubuntu Fedora Mint Debian over the network? Use sane-airscan!

I have a Canon MF642c and the scanner wouldn't work. I tried to use saned but it didn't work with the BJNPlike it did for some other Canon models. Introducing sane-airscan with packages for the most common distributions: https://software.opensuse.org/download.html?project=home%3Apzz&package=sane-airscan http........

How To Boot, Install and Run Windows 2000 on QEMU-KVM

Interestingly enough Windows 2000 works fine on QEMU 64-bit but you have to specify Pentium as your CPU otherwise it doesn't complete the install (it will not pass the detecting/setting up devices phase). -vga cirrus is wise because it is supported by Windows 2000 and allows higher resolutions and 24-bit color. -cpu Pentium emulates an old computer and is necessary for install to complete -device rtl8139 is important as this oldschool Realtek 8139 NIC is supported by W........

Linux Mint Ubuntu Debian Centos RHEL no sound solution

This assumes your system is a fresh and normally working install. What often happens is that many new devices have multiple audio outputs which are generally analog and HDMI/Digital out. Sometimes the OS defaults to the wrong one that you didn't want. For example if your sound is supposed to play over the HDMI, perhaps the output is set to analog or vice versa.........

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 ........

Linux How To Change NIC Name to eth0 instead of enps33 or enp0s25

Most newer distros inexplicably cause your NIC to have what Icall "random" non-standard name conventions because of systemd. This is a big problem for many people and especially those running servers. Imagine that you have a static IPconfigured for ens33 but then the hard disk is moved to a newer system, the NIC could be anything from ens33 to enp0s1, meaning that manual intervention is required to go and update the NIC config file (eg. /etc/network/interfa........

How To Speed Up Linux Ubuntu and Debian Based Computers By Improving CPU Performance and Changing the CPU Governor

I used to believe that for Desktops especially that the "ondemand" CPUfrequency changing that kernels included with Ubuntu and Debian based distros have would be sufficient for snappy performance. However, you can feel the lack of performance on the fastest computer if you have ondemand. A lot of times even under high load 100% of your CPUfrequency in MHz will not be used. For example a 2.8Ghz CPUmay only run at 1.8MHz or even .9GHz. Now........

mdadm: super0.90 cannot open /dev/sdb1: Device or resource busy mdadm: /dev/sdb1 is not suitable for this array.

mdadm --create /dev/md0 --level 1 --raid-devices 2 /dev/sdb1 missing --metadata=0.90 mdadm: super0.90 cannot open /dev/sdb1: Device or resource busy mdadm: /dev/sdb1 is not suitable for this array. mdadm: create aborted Sometimes running "partprobe" can fix this. Other times it requires a reboot. One other manual thing that can be done is the following to fix it (if dm is using and blocking it):........

OpenVZ vs LXC DIR mode poor security in LXC

It is unfortunate that LXC's dir mode is completely insecure and allows way too much information from the host to be seen. I wonder if there will eventually be a way to break into the host filesystem or other container's storage? OpenVZ better security: [root@ev ~]# cat /proc/mdstat cat: /proc/mdstat: No such file or directory /dev/simfs 843G 740G 61G........

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........

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........

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........

Linux delete unused tap devices automatically

This will find all tap devices and try deleting all of them. Of course don't run this if there is a chance an unused tap device is necessary and would not be created by the script ro application using it. for tap in `ifconfig -a|grep tap[0-255]|awk '{print $1}'`; do tunctl -d $tap done........

chroot in Linux Howto Simple and Easy Guide

chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk. So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1 The key point is to edit the &quo........

Cisco Router Setup Guide and Tutorial Howto With Commands and Examples

In most of the Cisco router IOS I find the ports like ge0/0 ge0/1 and ge0/2 or whatever your ports are down. They will not even give you a link light. So one of the first tasks should be getting the port you are working with up. In my case the first goal is often connectivity with the LAN and WAN. LAN = your local area network (eg. in the office/home ) WAN= your ISP/public internet (eg. fiber/cable/dsl/ethernet).........

proxmox vm networking breaks when you restart your network on the hostnode

Idid a systemctl restart networking and it broke Proxmox VM connectivity! #proxmox is the problem after restarting the network the tap devices go to disabled state [2230884.919905] vmbr0: port 7(tap118i0) entered disabled state [2230884.948864] vmbr0: port 8(tap122i0) entered disabled state [2230884.972748] vmbr0: port 6(tap119i0) entered disabled state [2230885.004745] vmbr0: port 5(tap117i0) entered disabled state [2230885.03673........

How to use nmap locate other machines/computers/servers on your network using nmap

A lot of people think arp wil do it but the arp table will only show devices you have communicated with. Using nmap is a quick and simple way to scan a range to find a machine you may not know the IP for: eg: nmap -sP 10.1.5.0/24 Just change the above to your subnet........

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........

iSCSI on Centos 7 Configuration and Setup Guide for Initiator and Target

initiator = client target = server These are the first concepts you should understand which is that in iscsi essentially the "initiator" is the client and the "target" is the server. iSCSI is derived from the old fashioned SCSI that us oldtimers grew to love. The "i" stands for Internet and the SCSI stands for "Small Computers Systems Interface" (SCSI). iSCSI Target (Server)Setup targetcli is the pac........

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.........

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 input/output error invalid program cannot read data on some CD-Rs and DVD-Rs on ASUS BW-16D1HT

I've never seen this before in all of my years. Ihave some very old CDs and DVDs 12-15 years old that seem not to work in this BD-R/DVD-R/CD-R Asus drive. The discs are fine actually and ironically they even work fine on a normal LG USB based BD-R drive! Here are the errors in Linux: [2914936.884924] attempt to access beyond end of device [2914936.884927] loop1: rw=0, want=730424, limit=688384 [2914954.556873] attempt to........

Linux how to view video card make and exact model

Normally lspci will show you just like this and would suggest they are exactly the same card: 1a:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7) 1c:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon RX 470/480/570/580] (rev e7) lspci -vnn is the answer As we can see one is a Gigabyte and the other is an MSI card. Wha........

How to Update Linux /usr/share/misc/pci.ids

This works with lspci and if it's outdated may not give you the exact manufacturer and device model. For example take these 3 different RX 580's: 1a:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 67df (rev e7) 1b:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 67df (rev e7) 1d:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Device 67df (rev e7) You ca........

pcimodules and lspci not working alternative solution

pcimodules no longer works it produces nothing probably because the format of /sys/bus/pci is different. lspci -k doesn't work on older lspci versions. pciutils can be compiled but it won't work if you have an old system and compile on a newer glibc. iteriate through /sys/bus/pci/devices/*/modalias cat /sys/bus/pci/devices/*/modalias pci:v00008086d00001237sv00000000sd00000000bc06sc00i00 pci:v00008086d00007000sv0000000........

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........

OpenVZ error : Container start failed (try to check kernel messages, e.g. "dmesg | tail") Locked by: pid 166638, cmdline vzctl start 888171

This container won't start after exhausting its memory. There are no relevant or helpful messages in dmesg or vzctl.log as well. Standard troubleshooting such as disabling PPP etc has not helped. 2017-07-06T23:33:29-0400 vzctl : CT 888171 : Locked by: pid 166029, cmdline vzctl start 888171 2017-07-06T23:33:29-0400 vzctl : CT 888171 : Container already locked 2017-07-06T23:33:29-0400 vzctl : CT 888171 : Container was stopped 2017-07........

USB 3.0 External HDD Enclosure Seagate UAS problems - [sdd] tag#1 CDB: Write(16) 8a 00 00 00 00 01 70 04 08 68 00 00 00 08 00 00

This is a 8TB Seagate external USB 3.0 device apparently newer kernels use a module called "UAS" instead of "USB Storage" which causes issues as a lot of devices are not properly supported in UAS mode by the kernel driver. The solution some say is to disable UAS specifically for your USB device but I'd rather just disable UAS altogether. Solution blacklist UAS: *do not do this it does not work and just causes your USB 3.0........

USB 3.0 PCI x1 Card Review VIA VL805 on Linux Review and Experience

This is a VIA made VL805 USB 3.0 Chipset with 4-ports and MOLEX powered. First of all this unit was cheap at about only 9 USD with fast shipping. My biggest concern was if this was a quality unit and would it really give you full USB 3.0 speeds (some people reported with similar cards that for some weird r........

USB Device/MP3 Player not working properly and can't browse the device filesystem? Check the cable twice and again!

Here is a simple MP3 player and now there's a reason to understand why the supplied cable has some kind of capacitor and is very short. These devices can be VERY finicky and any voltage fluctuation or difference is enough to cause issues. Take for example the error messages from Linux Mint: [804829.895414] usb 1-1: USB disconnect, device number 11 [806961.109030] usb 1-1: new high-speed USB device number 12 using xhci_hcd........

Apache SSL very slow response with Firefox Freezes/Loads Very slow when checking self-signed SSL certificate

I was sure this was a Centos bug with OpenSSL, Apache, MySQL or even PHP. I tried everything but nothing helped. One clue is that if you check the Apache logs you will see nothing in the access logs until minutes later (this means Firefox has not even passed your request to the remote Apache/htttpd server). When even accepting the invalid certificate message that would show up minutes later when trying to "View the Certificate" Firefox would freeze. This bu........

What happens when you unplug 1 or more devices from an mdadm RAID array to simulate a failure in Linux Ubuntu/Centos/Debian?

In short the two drives in the array were /dev/sdd and /dev/sde. The kernel sees they were unplugged and have gone down as you can see below. mdadm caught the first one being unplugged /dev/sde and disabled the missing drive. However when the final drive that was part of the array is unplugged it didn't notice at all. Instead it complains about an IO error later for drives that the kernel knows do not exist anymore. [45817.162728] ata4: exception........

Migrating from Linux Mint 17.2 mdadm RAID array to a new one (because I upgraded to larger drives).

1.) Replicate the number of partitions in your new drives. gdisk /dev/sda gdisk /dev/sdb I created 3 partitions of the same same size. partition #1: +1G (/boot) partition #2: +60G (swap) partition #3: rest of it (/) #note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........

mdadm frozen and doesn't realize array is dead/missing failed due to unplugged drives

This was a surprising bug but I unplugged all drives for an array md127. At first it was just 1 drive and mdadm seemed to notice this. I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it. This created problems trying to unmount it or even to stop this array with mdadm freezing. As for how to fix it I can only think of making sure you are not in a mounted path of........

mdadm kernel panic if trying to change --layout on a RAID10

It is already known this is not possible mdadm --create /dev/md3 --level 10 --layout=f2 --raid-devices=2 /dev/sdc1 /dev/sdd1 mdadm: /dev/sdc1 appears to be part of a raid array: level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016 mdadm: /dev/sdd1 appears to be part of a raid array: level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016 Continue creating ar........

DRBD Slow Performance - 99.99 % [jbd2/drbd0-8] highiowait solution

Tired of checking iotop and seeing that your drbd partition is using 99.99% of io all the time and finding your drbd device performs slow in general? This is especially an issue in versions of DRBD in the 8.3 tree in particular one documented case is on "8.3.13" but it likely applies to other devices. The symptoms are that resyncing is fine and normal but any reasonable amount of activity is very slow and lagged and creates a high server load and con........

OpenVZ Migration Hostnode Containers from Centos 5 to Centos 6

migrating from an old OpenVZ (Centos 5) to new OpenVZ (Centos 6) Also if migrating from 32-bit HN to 64-bit your RAM will probably be much bigger than it should be! 16x bigger eg. 32bit HN: total used free shared buffers cached Mem:&nb........

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:........

Linksys E2500 DD-WRT Upgrade Instructions and Enabling 5ghz with Tomato Firmware

1.) Flash directly to this file: http://tomato.groov.pl/download/K26RT-N/build5x-132-EN/Linksys%20E-series/tomato-E2500-NVRAM60K-1.28.RT-N5x-MIPSR2-132-Max.zip *I was never able to get the larger "Mega" file to work, at least not initially so I recommend the file above. To enable 5ghz I had to do the "Clear NVRAM" Option before it was shown. 2.) Or if you don't need 5ghz (most devices do not support it and cannot........

Errors were found while checking the disk drive for /.

Iwill start by saying I think I know what caused this boot-time error on Linux Mint but should also apply to Debian and Ubuntu. I changed my BIOS time to several hours in the past to match the current time, but this caused Linux to think there were incorrect filesystem times. The problem is that it seems when you hit this I am not sure what is happening, it doesn't seem to be doing fsck and hangs without prompting the user. What I have found is that........

Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling

Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........

How To Install Linux Mint 17.2 on mdadm RAID with a separate boot partition

Iwas surprised to see that Linux Mint at the latest 17.2 version still has NO mdadm installer option, and worse the installer will not be able to create a proper booting environment even when you do install it. How to setup mdadm in Linux mint LiveCD sudo su apt-get install mdadm # partition as you need and then create your mdadm devices # create your SWAP md0 mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /d........

ONVIF Linux Security Camera Setup

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[3805108.257042] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257052] sd 0:0:0:0: [sda] Write Protect is off [3805108.257054] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 [3805108.257066] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [3805108.257083] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257090] sd 0:0:0:0: [sda] Write Protect is off........

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[27969.398749] sd 5:0:0:0: [sdb] 3907029168 512-byte hardware sectors (2000399 MB) [27969.398749] sd 5:0:0:0: [sdb] Write Protect is off [27969.398749] sd 5:0:0:0: [sdb] Mode Sense: 00 3a 00 00 [27969.398749] sd 5:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [27972.117543] ata6.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [27972.117543] ata6.00: irq_stat 0x48000000 [27972.117543] ata6.00: cmd 60/08:00:ff:7........

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