Diagnosing problems with an OpenStack deployment
I recently had the chance to help a colleague debug some problems in his OpenStack installation. The environment was unique because it was booting virtualized aarch64 instances, which at the time did not have any PCI bus support...which in turn precluded things like graphic consoles (i.e., VNC or ...read more
Converting hexadecimal ip addresses to dotted quads with Bash
This is another post that is primarily for my own benefit for the next time I forget how to do this.
I wanted to read routing information directly from
bash, because you never know what may or may not be available
in the minimal environment of ...
Visualizing Pacemaker resource constraints
If a picture is worth a thousand words, then code that generates pictures from words is worth...uh, anyway, I wrote a script that produces dot output from Pacemaker start and colocation constraints:
You can pass this output to graphviz to create visualizations of your ...read more
Stupid Pacemaker XML tricks
Check if there are any inactive resources
pcs status xml | xmllint --xpath '//resource[@active="false"]' - >&/dev/null && echo "There are inactive ...
Unpacking Docker images with Undocker
In some ways, the most exciting thing about Docker isn't the ability to start containers. That's been around for a long time in various forms, such as LXC or OpenVZ. What Docker brought to the party was a convenient method of building and distributing the filesystems necessary for running containers ...read more