Blog of Junkin » Server Setup & Config

huge crashes with centos 6.2 & LSI SAS

jjunkin — Thu, 22 Dec 2011 23:26:48 +0000

Yesterday I ran yum update on most of my servers. It was a large update, I guess it was centos 6.2? At any rate part of the update was kernel /vmlinuz-2.6.32-220.el6.x86_64. After I updated 3 of my servers became unresponsive – which has never happened before. On the console I found strange error messages:

‘rejecting I/O to offline device’

and

‘task jbd2/sda3-8 blocked for more than 120 seconds’

Scary stuff! Googling around found a lot of mention of serious hardware issues. Bummer! I figured it would take a while to figure it out. Probably need to get new drivers for the LSI SAS and build the new module.

Then I wondered if it was maybe the new kernel from the update. I went into /boot/grub/grub.conf and changed the default from 0 to 1, which selects the prior kernel.

Reboot. Problem solved. Going home.

MegaRaid Manager (MSM) for the LSI 2108

jjunkin — Tue, 22 Nov 2011 23:17:14 +0000

I have the supermicro SuperServer 2026TT H6RF server. Each contains 4 nodes and each node has an onboard 6Gbps SAS controller, an LSI 2108. I wanted to install a manager for monitoring the drives and raid status.

Digging around I found:

ftp://ftp.supermicro.com/driver/SAS/LSI/2108/

which is the drivers and the MSM raid manager. I did not install the driver, centos 6 seems to utilize the SAS card just fine.

Upon unpacking the zip file:

ftp://ftp.supermicro.com/driver/SAS/LSI/2108/MSM/Linux/11.06-00/11.06-00.zip

I found in the disk directory the readme that has prerequisites for RHEL6. They list a bunch of rpms that need to be installed. I had the target packages installed via yum, but I got errors running the install script. It wasn’t clear what exactly I needed to install.

I think the pre-requisites are 32 bit libraries. At any rate after much fumbling around I found the MegaRaid manager worked when I installed the following yum packages:

yum install libstdc++.i686

yum install libXext.i686

yum install libXtst.i686

Good luck!

The best Servers(s) in the world

jjunkin — Thu, 09 Jun 2011 23:34:08 +0000

So you are a startup. You have decided to not use the cloudy stuff. You want some rocking hardware! Here it is.

Start with the chassis: The awesome Supermicro 2026TT. This badass in a 2U case has 4 nodes and can handle 24 2.5″ HDD’s. Each hot-swappable node has 2 sockets for Xeon processors 5600/5500, up to 196 Gig of ECC Ram and onboard LSI SAS 6g card to handle the max of six hot-swap drives.

Blades? We don’t need no … Who has the money for blades? This is an excellent startup box. Cost? For each node I configured: 48 G of ECC/REG RAM, 2 X 600G seagate HDD (to be added to later), 2X XEON E5620. I bought 2 of these servers for a total of 8 nodes. plus 2 extra drives for one of the boxes. $31,000 before tax. $31K for 8 rockin servers with 48G of RAM. This was on 12/2010.

Oh, and the redundant hot swap power supply consumes a max of 1400 watts which is 350 watts per server. Very low power for such beefy boxes. After 6 months of operation these supermicro boxes have been flawless. Still running CENTOS 5.

Hot swap node

Updated wordpress

jjunkin — Sun, 06 Sep 2009 05:43:30 +0000

Thanks to popurls, I happend to see the exploit warning for wordpress. I just went and updated all my wordpress sites. Thank god for subversion!

CVS server configuration

admin — Tue, 19 Dec 2006 21:23:02 +0000

I configured the CVS server on a remote fedora 6 (FC6) server today. It was a bit of a pain but only because of the lack of clear documentation. I needed a remote server to run CVS so that any client could checkout a project and then checking/update to a central server. The first thing I neeed to do was ensure that ssh between the client and server required no password. Otherwise it would be prompting me for a password at each ‘cvs’ command.

The first step was to configure the CVS repository on the cvs server:

cvs -d /var/cvs init

I chose /var/cvs because that seemed to be where fedora put it by default.

I next needed to setup server access which works through xinted. I assumed that I could set cvs up as a normal service in /etc/rc.d/init and manage it through chkconfig, but I was unable to find such a service (if anyone knows of one please let me know!) So I needed to install xinetd first:

yum install xinted

Â Next, edit the configuration for the cvs server under xinted by editing:

/etc/xinetd.d/cvs

Switch the service on by changing the line:

‘disableÂ Â Â Â Â = yes’Â to Â ’disable = no’

The rest of the config I left as default since I was using the default setup.

Then I started the xinetd server:

service inetd start

I tested the operation by opening a hole in the firewall for port 2401 and telnet’ing in.

For the client I edited my ~/.bash_profile and added a line for the cvs stuff

# tell cvs to use rsh
CVS_RSH=ssh
export CVS_RSH

# the path to the cvs executable on the remote machine

CVS_SERVER=/usr/bin/cvs
export CVS_SERVER

CVSROOT=”:ext:myUserName@cvsServerName:/var/cvs”
export CVSROOT #login replace myUserName and cvsServerName with appropriate settings

CVSEDITOR=”emacs -nw”Â # because vi sucks ass!
export CVSEDITOR