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  • hwloc-nox set CPU affinity in Linux


    sudo apt-get install  hwloc-nox Reading package lists... Done Building dependency tree       Reading state information... Done The following NEW packages will be installed:   hwloc-nox 0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded. Need to get 151 kB of archives. After this operation, 453 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubunt........
  • gvfs mount in /run/user cannot be accessed or displayed wrong permissions


    The folder contents could not be displayed Backend currently unmounting drwx------ 10 userhere group  260 Aug 23 19:40 .. ??????????  ? ?   ?      ?            ? sftp:host=192.168.8.80,user=adhoc ls: cannot access 'sftp:host=192.168.8.80,user=adoc': Input/output error $ ps aux|grep fuse one       253........
  • prosody xmpp server "Failed in all attempts to connect to proxy.eu.jabber.org"


    Aug 13 13:46:33 s2sout2d45040    info    Failed in all attempts to connect to proxy.eu.jabber.org Aug 13 13:46:33 s2sout2d45040    info    Sending error replies for 1 queued stanzas because of failed outgoing connection to proxy.eu.jabber.org No clue why it tries to use a proxy not explicitly specified.  This could be because the proxy specified for the domain fails when someone is trying to se........
  • gmail.com address failing in Postfix


    Aug 10 01:11:54 mailserver postfix/smtp[6180]: 020AE17C2BD1: to=<theuserperson@gmail.con>, relay=none, delay=0.29, delays=0.28/0/0/0, dsn=5.4.4, status=bounced (Host or domain name not found. Name service error for name=gmail.con type=A: Host not found) A user complained that their e-mails weren't being delivered but they actually made a small typo and used gmail.con so it wasn't working as expected of course........
  • FreeBSD/OpenBSD OpenVPN Client error "Cannot allocate TUN/TAP dev dynamically"


    I have never had this error on Linux and this is running FreeBSD as root: Wed Aug  9 04:29:34 2017 us=329050 Cannot allocate TUN/TAP dev dynamically Wed Aug  9 04:29:34 2017 us=329832 Exiting due to fatal error The Solution you need a kernel module that is for some reason not automatically loaded like Linux: kldload if_tap........
  • Cannot allocate TUN/TAP dev dynamically - FreeBSD/OpenBSD OpenVPN Client error Solution


    I have never had this error on Linux and this is running FreeBSD as root: Wed Aug  9 04:29:34 2017 us=329050 Cannot allocate TUN/TAP dev dynamically Wed Aug  9 04:29:34 2017 us=329832 Exiting due to fatal error The Solution You need a kernel module that is for some reason not automatically loaded like Linux: kldload if_tap........
  • 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........
  • grubby fatal error: unable to find a suitable template solution Centos


    vzkernel-2.6.32-042stab116.2.x86_64.rpm                                                                           &n........
  • Postfix Errors & Solutions "unprivileged": bad value: "???" - bad transport type:


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


    To first start off, there are many misconceptions about NoSQL and especially its strengths and weaknesses. Even the popular NoSQL solution MongoDB is fraught with issues that no one seems to be concerned about aside from a few but there are serious issues with database integrity and verified writes.  MySQL was considered dangerous or incomplete at one point without having the transactional safety features of Oracle for example. However the NoSQL implementations seem........
  • Unixbench Testing


    The first is a dual CPU AMD Opteron 2373EE (4 cores x 2) and I think it did bad because it has some old 250GB SATAs which can only do about 65 MB/s max sequential reads.  I think it should have blown away the second (AMD X4 640 Quad Core).   [root@fs12home unixbench-4.1.0-wht-2]# ./Run make all make[1]: Entering directory `/root/unixbench-4.1.0-wht-2' Checking distribution of files ./pgms  exists ./src  exists........
  • Dell Perc 6/i cannot downgrade


    I flashed an LSI Logic firmware to it and it broke the BIOS (cannot do Ctrl+R) for booting purposes but allows other functionality to work normally. I tried downgrading to a Dell firmware for Perc 6i but it won't work, not even with MegaCli wget http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN --2013-08-26 12:53:39--  http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN Resolvi........
  • Linux Out of Memory OOM Object Killer Solution "Out of memory: kill process 1955 (sshd) score 81 or a child"


    I had a system running a 128MB live CD image with 2.8 gigs of available RAM and the OOM kernel killer went crazy when using dd for more than 8 minutes and kept killing everything.  I've read that this is due to a low-memory issue and paging in the kernel and 32-bit systems with lots of RAM. I even enabled swapspace on my LiveCD and the issue happened 25 minutes into dd rather than 8 minutes, so what gives? Also no swap space was ever used! cat /proc/s........
  • Apache High CPU Usage Enable Mod_Status Guide Solution - Find Cause of High CPU Usage Script/Domain


    mod_status is a great way to track down the source of high CPU usage and to find what vhost/script is the cause of it. It gives you a live view of bandwith usage, CPU usage, and memory usage broken down by domain/vhost and script/URI. Enable mod_status vi /etc/httpd/conf/httpd.conf ExtendedStatus On <Location /server-status> SetHandler server-status Order Deny,Allow Deny from all All........
  • mdadm Linux Software RAID QuickStart Guide


      Create New RAID 1 Array: First setup your partitions (make sure they are exactly the same size) In my example I have sda3 and sdb3 which are 500GB in size. mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sda3 /dev/sdb3 mdadm: array /dev/md2 started. Check Status Of The Array *Note I already have other arrays md0 and md1. You can see below that md2 is syn........
  • Shutdown/Power/Halt In Debian/Ubuntu/Centos Guide Systems Doesn't Work


    Different distributions such as Debian and Centos behave differently when trying to shutdown your system. shutdown -H now on Debian does not do what you'd expect.  The system won't power down, it will halt and do everything but power down. shutdown -PH now will do the job though (actually power the system off).  This is important to test especially if you are not near the system.  If you just use -P it forcefully shuts off which is not........
  • Unixbench Score with Glusterfs/Openvz & Quad Core Xeon - Updated with GlusterFS 2.0.8


    You might remember my original GluserFS/OpenVZ benchmark which produced a horrible 29.8 This is the exact same system, but using the latest 2.0.8 (with some small files patch which speeds up performance) you can see it is about 25% faster. I also haven't tuned my config files at all, but there are some settings that should increase performance on small files which I believe i........
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