project-config/nodepool/elements
Ian Wienand c70cf77969 Update remote refs in early devstack clone
In another confusing addendum to
I41e81d6bac98875eecde2376e0865784626e11a8 (which was already a
confusing addendum to Ieb6a6e9f55bd93f63c3d0a71828c276c2d02e1b9), we
have decided that the refspec used to fetch here is not sufficient to
clear out remote branches everything when updating.

"+refs/heads/*:refs/heads/*" says to replicate everything from the
remote refs/heads into our local refs/heads, but leaves out
refs/remotes/*

The upshot of this is that I41e81d6bac98875eecde2376e0865784626e11a8
will remove the local branches (refs/heads/stable/icehouse, say) but
not remove the remote branches (refs/remotes/origin/stable/icehouse).
The devstack caching script keeps picking up these remote branches,
checking them out, and consequently trying to download old images.

*Nothing* ever removes these branches.  In the main dib cache git
update, we also have --prune, but our refspec there is even more
limited (+master:master).  This explains why these branches never seem
to die.

Note, an even better mirror would be "+refs/*:refs/*" (in fact, if you
do git clone --mirror, this is what the repo would be setup with to
fetch by default).  However, this drags in "refs/changes/*" and all
sorts of other gerrit things.  We don't really need them so we just
keep the limiting on.

Change-Id: Ia9c3ffdb2b5f72a45d629961338b415308d6dd21
2016-01-19 11:06:12 +11:00
..
cache-bindep Remove CentOS6 from nodepool scripts 2015-12-04 22:11:22 +01:00
cache-devstack Update remote refs in early devstack clone 2016-01-19 11:06:12 +11:00
node-devstack Add python3-dev 2015-10-22 15:08:28 +02:00
nodepool-base Increase memory restriction to 9023M 2015-12-15 10:32:06 -08:00
openstack-repos diskimage-builder element cleanups for dib-lint 2015-10-08 11:33:03 +11:00
puppet Install puppet using build_git system-config 2015-12-08 13:43:47 -08:00
slave-db Reorganizes project-config 2014-09-25 11:41:04 -04:00
README.rst Determine CentOS 6 platform in cache-devstack 2015-05-01 20:57:05 +00:00

Using diskimage-builder to build devstack-gate nodes

In addition to being able to just download and consume images that are the same as what run devstack-gate, it's easy to make your own for local dev or testing - or just for fun.

Install diskimage-builder

Install the dependencies:

sudo apt-get install kpartx qemu-utils curl python-yaml

Install diskimage-builder:

sudo -H pip install diskimage-builder

Build an image

Building an image is simple, we have a script!

DISTRO="ubuntu" bash tools/build-image.sh

See the script for environment variables to set distribution, etc. You should be left with a .qcow2 image file of your selected distribution.

It is a good idea to set TMP_DIR to somewhere with plenty of space to avoid the disappointment of a full-disk mid-way through the script run.

While testing, consider exporting DIB_OFFLINE=true, to skip updating the cache.

Mounting the image

If you would like to examine the contents of the image, you can mount it on a loopback device using qemu-nbd.

sudo apt-get install qemu-utils
sudo modprobe nbd max_part=16
sudo mkdir -p /tmp/newimage
sudo qemu-nbd -c /dev/nbd1 /path/to/devstack-gate-precise.qcow2
sudo mount /dev/nbd1p1 /tmp/newimage

or use the scripts

sudo apt-get install qemu-utils
sudo modprobe nbd max_part=16
sudo tools/mount-image.sh devstack-gate-precise.qcow2
sudo tools/umount-image.sh

Other things

It's a qcow2 image, so you can do tons of things with it. You can upload it to glance, you can boot it using kvm, and you can even copy it to a cloud server, replace the contents of the server with it and kexec the new kernel.