It seems that several people have been having problems getting Dell OMSA 6.2 to work correctly on CentOS 5.4 x86_64. Specifically, the software does not detect any storage controllers, and therefore also doesn't find any disks. eg.

[root@b034 ~]# omreport storage pdisk controller=0
Invalid controller value. Read, controller=0
No controllers found.

After a little investigation, I found the source of the problem.

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I've used subversion for quite a while now – I vaguely remember using CVS when working with some Sourceforge projects, but most of my experience is with subversion.

I've used the command svn status (or svn st, for short) to show me what changes there are in my working copy. However, I've occasionally thought it would be nice to see what updates are available in the repository but I've never bothered to find out how to do it. Until now…

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I'm using the net-snmp-lvs module to interface LVS statistics to SNMP so I can graph them (I'm using OpenNMS).

I have a virtual HTTP service that is balanced across eight real servers. In testing, everything seemed to work just fine and I got some nice graphs that show the Connection Rate, Packet Rate, and Byte Rate for the virtual service and each of the real servers.

This morning, we attempted a cutover, ie. we re-directed real traffic to the new service. Sadly, our perimeter firewall hit > 90% CPU so we had to revert. But, in the time that we were live, I noticed that the Connection Rate statistics were missing for both the virtual service and the real servers for the period in which the service was under high load:

LVS Connection Rate

LVS Packet Rate

LVS Byte Rate

Notice the gap in the Connection Rate graph when the Packet & Byte rate graphs show high values.

I am currently investigating the cause of this issue.

As I mentioned in a previous post, the MySQL RPMs provided for RHEL/CentOS by percona are not actually compatible with RHEL/CentOS. They use the same package layout as the MySQL-provided RPMs.

Here's how I create my own RPMs having the same package layout as the RHEL/CentOS packages but with the percona highperf patchset applied.

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ourdelta provide MySQL packages for various platforms, built with assorted performance/feature patchsets.

Sadly, like the percona builds, the RPM packages for RHEL/CentOS are not upstream-compatible, ie. they package MySQL differently.

I was planning to re-build the ourdelta packages to use the upstream RPM package layout but I've decided to stick with re-building the percona packages as I've already done the work for that.

Anyway, in case it helps someone, here's how to rebuild the ourdelta packages from the SRPM:

rpmbuild --rebuild \
  MySQL-OurDelta-5.0.87.d10-65.el5.src.rpm \
  --define 'ourdelta 1' \
  --define 'mysqlversion 5.0.87' \
  --define 'elversion 5' \
  --define 'patchset d10'

I use puppet to distribute my sshd configuration, including pre-generated ssh certificates.

Here's how I bulk create certificates for a bunch of new nodes named b001-b034:

for n in $(seq -w 1 34); do
    ssh-keygen -q -t rsa -f b0$n -C '' -N ''
done