Linuxcon day three, Wednesday

After hacking away on Monday and Tuesday and meeting fellow nerds IRL, I’ve landed even more changes to puppet-gluster. My git master branch now sits at 47 commits.

$ git clone https://github.com/purpleidea/puppet-gluster.git
Cloning into 'puppet-gluster'...
remote: Counting objects: 317, done.
remote: Compressing objects: 100% (144/144), done.
remote: Total 317 (delta 187), reused 275 (delta 148)
Receiving objects: 100% (317/317), 82.17 KiB | 12.00 KiB/s, done.
Resolving deltas: 100% (187/187), done.
$ cd puppet-gluster/
$ git log | grep '^commit' | wc -l
47
$ git log | head
commit fa3fd2eb4bab499031274e0918a40e7a99fe0086
Author: James Shubin <hidden>
Date:   Wed Sep 18 17:53:13 2013 -0400

    Added fancy volume creation.
    
    This moves the command into a separate file. This also adds temporary
    saving of stdout and stderr to /tmp for easy debugging of command
    output.

As you can see above, volume creation is now “fancier” and more robust. In case things go wrong, it’s easy to get fast access to gluster command line output (saved in /tmp/), and the volume creation commands are individually stored in your puppet-gluster working directory. Usually this is /var/lib/puppet/tmp/gluster/, and each volume creation command is in the volume subdirectory.

I also met gluster expert Joe Julian. He’s been recently hired at Rackspace. Congratulations Joe. We talked about puppet and gluster, and is very knowledgeable about gluster internals and PRN source diving.

I was interviewed by Aaron Delp and Brian Gracely, on The Cloudcast. These two gentlemen are a pleasure to sit and chat with. Check out their podcast. We talked about puppet, gluster, puppet-gluster and how to dive in. Feel free to comment or email me if you have any questions about something that we didn’t cover in the interview.

All week, I’ve been hacking along side Jayneil Dalal in the speaker room. He was kind enough to give me a Beagle Bone black! Where will its hack potential take you? Two features which are particularly useful are on-board Ethernet, and 2GB of flash storage. He’s at the conference showing off some Minnow boards. They’ve got an Intel atom chip on board if you need something a little beefier.

I’m giving my puppet-gluster talk tomorrow (Thursday) here at Linuxcon! I hope you can make it. I’ll even have a live demo. Until then,

Happy hacking,

James

Linuxcon day two, Tuesday

Continuing on from yesterday, I’ve met even more interesting people. I chatted with Dianne Mueller about some interesting ideas for gluster+openshift. More to come on that front soon. Hung out with Jono Bacon and talked a bit about puppet-gluster on Ubuntu. If there is interest in the community for this, please let me know. Thanks to John Mark Walker and RedHat for sponsoring me and introducing me to many of these folks. Hello to all the others that I didn’t mention.

On the hacking side of things, I added proper xml parsing, and a lot of work on fancier firewalling to puppet-gluster. At the moment, here’s how the firewall support works:

1. Initially, each host doesn’t know about the other nodes.
2. Puppet runs and each host exports host information to each other node. This opens up the firewall for glusterd so that the hosts can peer.
3. Now that we know which hosts are in a common pool, we can open up the firewall for each volume’s bricks. Since the volume has not yet been started (or even created) we can’t know which ports are needed, so all incoming ports are permitted from other gluster nodes.
4. Once the volume is created, and started, the TCP port information will be available, and can be consumed as facts. These facts then refine the previously defined firewall rules, to only allow the needed ports.
5. Your white-listed firewall setup is now complete.
6. For users who wish to avoid using this module to configure your firewall, you can set shorewall => false in your gluster::server class. If you want to specify the allowed ip access control manually, that is possible too.

I hope you find this useful. I know I do. Let me know, and

Happy Hacking,

James

Linuxcon day one, Monday

I’m here in New Orleans at Linux Con, hacking on puppet-gluster and talking to lots of interesting folks. I’ve met gluster hacker Theron Conrey, and my host John Mark Walker, Fedora and Raspberry Pi experts Spot and Ruth Suehle, and many others too.

The hotel is very nice. The bathroom sink has two taps of course, but both of them are hot. The New Orleans heat is probably the cause of this.

I’m hacking at full speed to get some new features and testing in before my talk on Thursday. I’ve been reworking the simple firewall support in my puppet module. For those that want automated and correct firewall configuration, expect some improvements soon.

I also pushed some work on property management for gluster volumes. This commit adds a list of all available gluster properties. The patch is still missing type information for many of them, because I haven’t yet tested each one, but if there are some you’d like to use, please let me know. This is easy to patch.

More code is landing soon. Don’t be afraid to contact me if you’re not sure how to get started with puppet gluster, or if there’s a use case that I am not currently solving.

Happy Hacking,

James

PS: Sorry I published this late!

New puppet-gluster features before Linuxcon

Hey there,

I’ve done a bit of puppet-gluster hacking lately to try to squeeze some extra features and testing in before Linuxcon. Here’s a short list:

• SELinux fixes to keep Dan Walsh happy :)
• Ping and status checks before volume creation. Now puppet-gluster will be less noisy about failures or missing executions that are due to the necessary incremental nature of puppet-gluster runs. You’ll need multiple puppet runs to get a complete setup, so don’t let puppet complain part way through. This is due to the design of puppet.
• Simple filesystem paths for bricks. This is very useful for prototyping with virtual machines.
• Automatic UUID assignment for hosts. This requires exported resources.
• Updated examples
• And more…

If there are features or bugs that you’d like to see added or removed (respectively) please let me know ASAP so that I can try to get something ready for you before my Linuxcon talk. I also don’t have any hardware RAID or physical hardware to test external storage partitions (bricks) on. If you have any that you can donate or let me hack on for a while, there are some features I’d like to test. Contact me!

I’ve got a few more things queued up too, but you’ll have to wait and see. Until then,

Happy hacking,

James

Puppet-Gluster and me at Linuxcon

John Mark Walker, (from Redhat) has been kind enough to invite me to speak at the Linuxcon Gluster Workshop in New Orleans. I’ll be speaking about puppet-gluster, giving demos, and hopefully showing off some new features. I’m also looking forward to meeting up with gluster expert Joe Julian.

If there are features that puppet-gluster is missing, or you have a use case that I haven’t covered, please let me know, and I’ll try to work on it for you ahead of the conference. If you want to meet up for some puppet-gluster help, or to hack on code, I’ll be around from the 16th to the 20th of September. My talk is on the 19th.

Special thanks to John Mark and Redhat for sponsoring this trip. Without them, none of this would be possible.

Happy hacking,

James

Finding YAML errors in puppet

I love tabs, they’re so much easier to work with, but YAML doesn’t like them. I’m constantly adding them in accidentally, and puppet’s error message is a bit cryptic:

Error: Could not retrieve catalog from remote server: Error 400 on SERVER: malformed format string - %S at /etc/puppet/manifests/foo.pp:18 on node bar.example.com

This happens during a puppet run, which in my case loads up YAML files. The tricky part was that the error wasn’t at all related to the foo.pp file, it just happened to be the first time hiera was run. So where’s the real error?

$ cd /etc/puppet/hieradata/; for i in `find . -name '*.yaml'`; do echo $i; ruby -e "require 'yaml'; YAML.parse(File.open('$i'))"; done

Run this one liner on your puppetmaster, and hiera should quickly point out which files have errors, and exactly which lines (and columns) they’re on.

Happy hacking,

James

 

Upgrading from Fedora 18 to Fedora 19

It was time to take the plunge and upgrade from Fedora 18 to Fedora 19. Fedora 18 was one of the worst releases ever, so I figured it could only get better. I ran my backups as usual, however this time I didn’t seem to need them, the upgrade process went off without a hitch! I used the fedup-cli process over the network. I always run these things inside of screen.

Here are my post install notes and comments:

Brown folder icons:

Someone broke the icon theme, and folders are now an ugly brown. Even though you’ll see a “Fedora” entry in the GNOME tweak tool, icon theme section, it won’t work. You need to install a theme package first:

# yum install fedora-icon-theme

tweak tool will now let you fix the brown icon issue.

Dash doesn’t launch new windows:

The GNOME shell is back to its old habit of trying to imitate Mac OSX. Thankfully there’s an official extension to fix this: https://extensions.gnome.org/extension/600/launch-new-instance/

If you search for “Classic Mode” on https://extensions.gnome.org/ you’ll find some other useful add ons. You might enjoy: AlternateTab, AvoidOverview, and SystemMonitor.

Evolution is snappier:

Congratulations to the evolution developers, this release seems a bit snappier! I haven’t tested it thoroughly, however closing evolution now happens in under ten seconds! Usually it would either hang or take much longer to close. Keep up the good work!

Clocks deletes your old clocks:

The clocks application deleted all the clocks that I had added. I suppose there are worse forms of data loss, but this is still pretty unprofessional! I had added one for every new place I had visited. Goodbye memories!

YUM breaks pexpect scripts:

A new version of YUM, now prompts you differently:

# yum install foobar[...]
Is this ok [y/d/N]:

No it’s not okay that you’re confusing my brain by adding a d. I actually don’t have any pexpect scripts depending on this, but after years of seeing y/N, the change is not welcomed. It should have been handled with a YUM download target instead.

Password prompts are annoying:

The GNOME shell handles most of the password prompts. This makes sense because it can help prevent you typing your password into a chat room. The problem is that if you need to run an external password manager to find a password, you’re out of luck. Maybe someone can add an option to minimize the focus stealing window. In addition, the “remember password” checkbox should NOT be on by default! It still is for evolution, and perhaps other apps too.

GNOME shell isn’t smooth, but it’s better:

Fedora 17 provided a smooth GNOME shell experience. Fedora 18, somehow killed the performance, and no fixes could be found. The performance seems to be a bit better in Fedora 19, but it’s still not perfect. Drivers are probably partly to blame.

New version of Gedit breaks some things:

The Gedit dashboard plugin no longer seems to work. After debugging the issue, it seems to be a packaging problem. To fix:

# yum install python3-dbus

and dashboard should work when enabled. The gedit-autotab plugin is thoroughly broken. I’d love to get that working again for smarter spaces!

That’s all for now,

Happy hacking,

James