Older blog entries for skvidal (starting at number 459)

polling/diffing instances in openstack

I’m trying to produce a simple list of instances on the fedora

openstack instance. I want to produce a list every 10m or so and diff

it against the last copy of that list and output the changes.

Here’s what I came up with:
http://fedorapeople.org/cgit/skvidal/public_git/scripts.git/tree/openstack/gather-diff-instances.py

it is based originally on nova-manage. It runs as root on the head system in our cloud and just dumps out json, then diffs the json.

Everything works but I’m trying to figure out if this is the ‘right’
way of going about this.
I thought about doing it via nova instead of using the nova-manage
direct-to-db api but I had 2 problems:

1. I would need to save the plaintext admin pw somewhere on disk to
poll for that info

2. or get a token which I would have to renew every 24 hours

We’re using the above the script as a simple cron job that lets us know
what things are changing in our cloud (who is bringing up new
instances, how many, what ips they are attaching to them, etc)

Additionally, is there a way in the db api to easily query the tenant and user info from keystone? I’d like to expand out the user uuid into username/project name.

 

 

Syndicated 2013-03-27 04:04:40 from journal/notes

gitproxy

gitproxy:
http://skvidal.fedorapeople.org/misc/gitproxy

Dealing with a potential problem we were trying to figure out a way to proxy/redirect git:// calls from one server to another one. This is a fairly ridiculous script I hacked up in the wee-small hours of thursday morning after talking to+Sitaram Chamarty on #git  for a while.

I fully expect this won’t work well under load but it does seem to function in my small tests here.

 

 

Syndicated 2013-03-22 19:01:07 from journal/notes

diffing two ini files

Ever need to diff 2 ini files but their sections and options aren’t in the right order?

Well, I do. I googled but I couldn’t find anything trivially available that did this.

I swear I wrote this once before but I couldn’t find it when I looked through my dirs of misc scripts so:

http://fedorapeople.org/cgit/skvidal/public_git/scripts.git/tree/inidiff

hope it is useful to someone.

Syndicated 2013-03-22 16:24:32 from journal/notes

async actions in ansible playbooks

A number of people have been surprised by this feature, even though it is documented, so I thought I’d mention it.

Ansible can run actions async. This means it connects to the client system, starts the process and disconnects.

In general you would want all your plays to be synchronous (do thing X, wait for it to be done/watch it, do thing Y).

However, there are times when what you want to do will take a VERY long time or could kill your ssh connection off.

An example is a yum update:

tasks:

- name: yum update

action: command yum -y update

That can take a long time, depending on what’s going on. You want to monitor what it does, but you don’t want a timeout or a reset ssh session/network to kill off that process.

So what do you do? You make it async:

tasks:

- name: yum update

action: command yum -y update

async: 7200

poll: 15

That means – run yum -y update – wait for up to 7200s and poll every 15s to check on the status of the action.

Here’s where we’re using it in fedora:

http://infrastructure.fedoraproject.org/cgit/ansible.git/tree/playbooks/package-update.yml#n11

However, this means if your ssh or network were to die – the yum update process would still run to completion.

But if your connection does die and you cannot check on the status of the job what do you do?

Well -you can connect to any system as the user who was running the job and look in ~/.ansible_async

there will be a file in there for each job that was being run. It may just be a place holder and empty (if the job is still running) or it made be filled with the results if the job is finished.

Pretty handy for a variety of tasks.

 

Syndicated 2013-03-07 00:49:49 from journal/notes

openstack and resizing qcow-based instances

So – the trick with resizing a qcow based instances is this:

1. either you have to resize the partitions in the initramfs of the instance (which is not yet available as something we can easily do, but we’re working on it

2. you have to resize the partition on the live instance and then reboot the instance.

Since 1 is going to take more time/testing – I went ahead to make 2 as painless as possible.

using the cloud-utils and ansible I came up with this:

http://skvidal.fedorapeople.org/misc/openstack-qcow-disk-resize.yml

Put in the hosts you want to run it against. It installs cloud-utils, resizes the partitions using growpart, reboots, waits for the instance to come back alive, then does the fs resizing.

I timed it – it took a total of 1m2s and that includes installing cloud-utils, waiting at minimum 10s for the instance to reboot and then resizing the  actual fs.

The example I gave checks the values from growpart – so it  won’t run more than once (and it won’t run if you cannot resize). So you can run this play over and over and not reboot it all the time. I’m thinking I’ll probably include this as a tasklist for a quick instance provisioning playbook.

 

Syndicated 2013-02-21 22:37:55 from journal/notes

1 step forward 2 steps back? openstack and img creation suck

dealing with image creation in all clouds is completely full of suck. I’d more or less come to terms on it with euca but now I’m trying to do the same thing with openstack and encountering some super-duper happy fun times.

I have a rhel6 img which works and boots – it is qcow2 based so it handles kernel updates, etc properly, yay. However it handles resizing  the / filesystem exactly not at all.

If I make the rhel6 img an ami and upload kernel/ramdisk – it’ll resize (well dump it out) into a large filesystem – no problem – but it handles kernel updates not at all.

 

I would like to have both, I think I deserve to have both, i’ll be damned if any of my testing comes up with both. I’ve done a fair amount of googling and LOTS of things I’ve found say that the qcow2 or raw img should just work in either openstack essex or folsom but I am not having that experience.

Anyone have a suggestion?

Syndicated 2013-02-20 05:52:12 from journal/notes

hubris

Is thinking that because something is working well that it will continue to do so.

 

Silly me.

 

 

Syndicated 2013-02-19 18:43:15 from journal/notes

coprs and buildsystems and a question I was asked today.

Work continues on coprs but today someone asked me if I knew of a simpler buildsystem that would let them spin up a builder, stuff a bunch of packages at it, and return a pile of results.

I said well… ansible and mockremote could do it.

I started thinking about HOW that would work and realized I have all the pieces – but not a lot of motivation to put it together at the moment.

So I thought I’d tell folks how I would do it and maybe someone will:

 

1. write a playbook to spin up an instance in one of the public clouds using ansible and it’s ec2 module:

http://skvidal.fedorapeople.org/misc/ansible-euca-transient.yml

2. then provision the system with mock, a mockbuilder user and mockchain.

3. tell the user the ip the instance has

4. user submits jobs to it with:

mockremote.py -r chroot -b ip –destdir=/somewhere/ -c –recurse pkg1 pkg2 pkg3

5. user comes back whenever it feels like it

6. user runs a terminate playbook like:

http://infrastructure.fedoraproject.org/infra/ansible/files/copr/provision/terminatepb.yml

which shuts down the instance they had spun up.

I can see wrapping that whole thing in a single script or just letting the user do it a bit at a time. Either way – trivial to setup your own personal, temporary and pristine builder.

 

Syndicated 2013-02-01 21:38:17 from journal/notes

coprs and fudcon

I’m still working on recaps from fudcon but I wanted to mention this to anyone who asked:

 

If you asked for access to coprs and you haven’t received a reply from me that is b/c I forgot that you asked. Please drop me an email and I can add you.

 

Thanks

Syndicated 2013-01-22 16:53:16 from journal/notes

copr status

We’ve gone through about 45 individual builds of a goodly number of pkgs thanks to the help of the testing volunteers. We’ve found a bunch of bugs and fixed many of them.

Here’s what’s changed:

1. we’re working on cli for copr – more info in this thread: https://lists.fedorahosted.org/pipermail/copr-devel/2013-January/000216.html

2. we’ve got some mockups from the UI team which should help mold where things can go

3. better logs and results for multiple builds

4. I took a first cut of an outline for setting up copr: http://git.fedorahosted.org/cgit/copr.git/tree/copr-setup.txt

 

Syndicated 2013-01-15 20:12:03 from journal/notes