[SOLVED] Post Newton to Ocata upgrade jumbo frame MTU isn't set by neutron linuxbridge agent

After upgrading from Newton to Ocata my agent's wouldn't set mtu 9000 on the tap interfaces of my vm's.  I asked around in IRC after unsuccessful googling and haleyb suggested a couple of recent backports.   https://review.openstack.org/#/c/475308/ and https://review.openstack.org/#/c/459729/

After downloading the patch files and patching with patch -p1 -d /usr/lib/python2.7/site-packages --verbose < 46e6dd57.diff it started working again.  I'm not entirely sure if it was both patches or just the simple order of operation patch that fixed it.  Either way problem solved for now.

Jinja templating trick for use with Salt and OpenStack transport_url

Openstack is moving to using a transport_url instead of discrete rabbitmq servers, username, and password settings.  This makes doing templating with a configuration management like salt, my personal favorite, problematic as you need to interlace sensitive passwords in a string of arbitrary length.  The best I could come up with is this:

{% set rabbit_credential = ['openstack',pillar['openstack_rabbit_pass']]|join(':') %}
{% set rabbit_hosts_list = pillar['rabbit_hosts'].split(',') %}  

...

            transport_url: rabbit://{% for item in rabbit_hosts_list %}{{rabbit_credential}}@{{item}}:5672,{% endfor %}

The secret is that a transport url can end in a comma without causing any problems.

SOLVED: Zenoss overview disappears in Firefox

I had a very strange disappearing overview in Zenoss when using Firefox. Turns out I had zoomed in at some point in time and on subsequent visits during Firefox's attempt to resize the text everything would disappear. Turns out all you need to do to get your Zenoss back in shape is to View->Zoom->Reset.

SOLVED: hpacucli Error: No controllers detected.

It would seem that HP doesn't care to acknowledge the existence of 3.0 or newer kernels with their array configuration tool hpacucli. The solution is to lie to the tool with a custom uname wrapper that can be found here: http://mirror.anl.gov/pub/linux/kernel/people/ak/uname26/

Failing install with kvm, need to jump to annother virtual console?

When installing under KVM it is sometimes useful to switch to another virtual console to trouble shoot. The problem is it is not obvious how to do this when using JollysFastVNC on a mac. The trick is to disconnect and adjust the "Keyboard Input" under the connection settings to "Immersive", this will make the function keys work as they would if you had a real console. You do not need to use the "fn" key as you would normally do in osx. Once this change is made and you have reconnected switching the virtual console is just a alt-fn key.

Jumbo Frames and Xen don't mix well

It seems that while the pethN and ethN in a dom0 can be set to support jumbo frames the bridge that connects them cannot. Some symptoms are ssh works but scp does not, pings the size flag set to overflow the standard 1500 mtu fail, ifconfig xenbr0 mtu 9000 fails. This was tested with xen 3.1 and rhel5.

Copying dumps from Postgres to MonetDB

When moving bulk data from postgres to monetdb you can use the psql \copy directive and the mclient copy like so:

psql:
\copy gftp_packets to 'my dump file' with csv
mclient:
copy into gram_packets from 'my dump file' delimiters ',','\n' ;

Booleans don't work, but a little python will fix it up:

fin = open('my dump file', 'r')
fout = open('my new dump file', 'w')
falserep = (x.replace(',f,',',0,') for x in fin)
truerep = (x.replace(',t,',',1,') for x in falserep)
for line in truerep: fout.write(line)

I was too lazy to fix the problem with successive booleans, so I just rinsed and repeated until all the t's and f's were 0's and 1's.