Contrary to most posts online that say you can only boot from a partition on RAID1, not RAID10, after setting up both partitions on RAID10, I was able to boot just fine. There may be a difference between RAID10 in an n=2 (2 [...]]]> http://thern.org/linux-and-freebsd/linux-desktop-or-server-with-md-raid-10/feed/ 0 http://thern.org/system-administration/minimizing-downtime-associated-with-webdnsmail-ip-address-migrations/ http://thern.org/system-administration/minimizing-downtime-associated-with-webdnsmail-ip-address-migrations/#comments Sat, 03 Apr 2010 00:45:34 +0000 Eric Thern http://thern.org/?p=201 Migrating servers to new datacenters or IP addresses is never entirely problem free, usually due to many DNS servers on the internet not obeying TTL’s or caching old records for way too long.

These old cached DNS records (usually at different ISP’s, major mailservers like google, hotmail, yahoo, etc.) cause problems where they’ll route mail [...]]]> http://thern.org/system-administration/minimizing-downtime-associated-with-webdnsmail-ip-address-migrations/feed/ 0 http://thern.org/linux-and-freebsd/vmware-2-0-x-and-centos-5-4-glibc-crashes-and-instabilities-a-workaround-solution/ http://thern.org/linux-and-freebsd/vmware-2-0-x-and-centos-5-4-glibc-crashes-and-instabilities-a-workaround-solution/#comments Fri, 05 Mar 2010 08:38:23 +0000 Eric Thern http://thern.org/?p=191 If you’re running VMWare Server 2.0.x on CentOS 5.4, you’ll have noticed that you (most likely) suffer random reboots and other instabilities on the guest operating systems – this is due to a glibc error in vmware’s libraries, and has yet to be fixed by vmware (thanks a lot).  The real issue is CentOS/Redhat has [...]]]> http://thern.org/linux-and-freebsd/vmware-2-0-x-and-centos-5-4-glibc-crashes-and-instabilities-a-workaround-solution/feed/ 1 http://thern.org/linux-and-freebsd/yum-update-check-script-runs-via-crontab-and-emails-when-new-updates-are-available/ http://thern.org/linux-and-freebsd/yum-update-check-script-runs-via-crontab-and-emails-when-new-updates-are-available/#comments Fri, 19 Feb 2010 05:03:32 +0000 Eric Thern http://thern.org/eric/?p=160 Here’s a quick script that will check yum updates and email you when there are new updates available.

Split into two sections, one script is for all package updates, and the other script is for letting us know if we need to reboot when a new kernel package has been installed.

Script to check for [...]]]> http://thern.org/linux-and-freebsd/yum-update-check-script-runs-via-crontab-and-emails-when-new-updates-are-available/feed/ 0 http://thern.org/linux-and-freebsd/logrotate-tweaks-to-enhance-rsync-backups/ http://thern.org/linux-and-freebsd/logrotate-tweaks-to-enhance-rsync-backups/#comments Sun, 22 Nov 2009 08:19:55 +0000 Eric Thern http://thern.org/eric/?p=109 logrotate, by default (at least on CentOS as of 3, 4, and 5.x), rotates logs by incrementing all numbers on previous logs by one, and moving the current log to log.0

This is all fine and good if you like your logs to all be rotated in order, and have a certain number backed up:

Useful to upgrade to newest security releases.

#!/bin/bash
#
# updates cache of VZ
#
#

#
# Set These (or pass from command line as below)
#
#TEMPLATE=centos-5-i386-afull
VZID=5999
#
# use this from command [...]]]> http://thern.org/linux-and-freebsd/openvz-cache-update-script/feed/ 0 http://thern.org/linux-and-freebsd/plesk-9-x-overuse-policy/ http://thern.org/linux-and-freebsd/plesk-9-x-overuse-policy/#comments Thu, 08 Oct 2009 09:25:35 +0000 Eric Thern http://thern.org/eric/?p=82 Parallels, in their infinite wisdom, introduced new “overuse” policies into their Plesk control panel as of version 9.0.  A great idea when just starting out, but a nightmare when upgrading from a previous version, since it changes the default behavior when clients and domain owners reach their pre-assigned limits.  Now, instead of just warning that [...]]]> http://thern.org/linux-and-freebsd/plesk-9-x-overuse-policy/feed/ 2 http://thern.org/linux-and-freebsd/upgrading-mailscanner/ http://thern.org/linux-and-freebsd/upgrading-mailscanner/#comments Wed, 07 Oct 2009 08:38:32 +0000 Eric Thern http://thern.org/eric/?p=75 Easy Upgrading of MailScanner – RPM version

(For Redhat/Centos – updated from the MailScanner documentation)
1) Make a backup copy of your current MailScanner (Linux):

cp -a /etc/MailScanner /etc/MailScanner.$(date +%Y%m%d)
cp -a /usr/lib/MailScanner /usr/lib/MailScanner.$(date +%Y%m%d)
cp -a /usr/sbin/MailScanner /usr/sbin/MailScanner.$(date +%Y%m%d)

2) Download the latest version and extract

http://mailscanner.info/downloads.html

Check [...]]]> http://thern.org/linux-and-freebsd/upgrading-mailscanner/feed/ 0 http://thern.org/linux-and-freebsd/dell-1650-server-and-ipmi-support-on-centos-5/ http://thern.org/linux-and-freebsd/dell-1650-server-and-ipmi-support-on-centos-5/#comments Thu, 17 Jan 2008 22:25:54 +0000 Eric Thern http://thern.org/eric/?p=64 So I bought a Dell 1650 server on ebay for cheap. I loaded it up with three 36gb U160 10,000 RPM SCSI disks in a RAID 5 array, loaded up CentOS 5 and off I went.

Once it was at the data centre, I wanted to monitor the system a bit. This meant I wanted [...]]]> http://thern.org/linux-and-freebsd/dell-1650-server-and-ipmi-support-on-centos-5/feed/ 0 http://thern.org/linux-and-freebsd/sendmail-premissions-error-stopping-mail-from-sending-on-centos-5-1/ http://thern.org/linux-and-freebsd/sendmail-premissions-error-stopping-mail-from-sending-on-centos-5-1/#comments Wed, 16 Jan 2008 22:24:11 +0000 Eric Thern http://thern.org/eric/?p=62 Really stupid issue with permissions on CentOS 5.1 and real easy fix, since there were improper permissions on the mqueue and clientmqueue directories.

The Error message:

Tried to send mail via command line using ‘mail’ command, and it returned this error:

can not chdir(/var/spool/clientmqueue/): Permission denied
Program mode [...]]]> http://thern.org/linux-and-freebsd/sendmail-premissions-error-stopping-mail-from-sending-on-centos-5-1/feed/ 0