Sorry for the late reply. I was on leave and after this some problems at my 
work.

> On 3 Sep 2020, at 17:23, Jehan-Guillaume de Rorthais <[email protected]> wrote:
> 
> Hi,
> 
> Thanks for sharing.
> 
> I had a very quick glance at your project. I wonder if you were aware of some
> existing projects/scripts that would have save you a lot of time. Or maybe you
> know them but they did not fit your needs? Here are some pointers:
> 
> # PAF vagrant files
> 
>  PAF repository have 3 different Vagrant files able to build 3 different kind
>  of clusters using libvirt.
>  I'm sure you can use Vagrant with Virtualbox for your needs.
> 
>  for a demo:
>  
> https://blog.ioguix.net/postgresql/2019/01/24/Build-a-PostreSQL-Automated-Failover-in-5-minutes.html

Vagrand was the secondary my attempt after Docker. I didn't not use it, because 
I didn't know that it can be used with libvirt and pure virtual machines. I 
need a pure VM, because I need in my schemas a watchdog device, at least the 
softdog.

Also one of the my tasks was to create a prototype for an automatic 
installation system, which latterly can be converted to Ansible, Salt, Puppet 
or Chef (sysadmins didn't know what to prefer). So the prototype of the 
automatic installation system was written on the pure bash. Installation is 
performed by the standard installation CentOS DVD image (or may be other RedHat 
compatible) and RedHats so called "kickstart" (implemented by VirtualBox). But 
Vagrant need the special preinstalled linux image, as far as I can understand, 
so it can not be used for prototyping an automatic installation system for real 
servers.

As for the automatic test system, yes, I think it can be rewritten to work with 
libvirt instead of VirtualBox. I don't see reasons why not. "PAF vagrant files" 
doesn't have an automatic test system, there is only possibility for manual 
testing. An automatic test system is important to look for low probable 
instability, to check new version of software or to play with setup parameters. 
So I can say that this step I already passed 2 years ago.
 
> # CTS
> 
>  Cluster Test Suite is provided with pacemaker to run some pre-defined failure
>  scenario against any kind of pacemaker-based cluster. I use it for basic
>  tests with PAF and wrote some doc about how to run it from one of the Vagrant
>  environment provided in PAF repo.
> 
>  See:
>  
> https://github.com/ClusterLabs/PAF/blob/master/extra/vagrant/README.md#cluster-test-suite

Interesting, this is looked like attempt to achieve the same goal, but with 
different method. What is the differences:

CTS uses Vagrant, while I imitate a kickstart automatic installation on real 
servers. CTS is written on python, I use bash. They concentrate on testing the 
pacemaker functionality, for instance start/stop nodes in different orders. 
While I concentrate on tests that imitate hardware failures (for instance 
unlink) or other catastrophic failures (out of space, etc). They wrote an 
universal pacemaker test, but my tests more special for the 
pacemaker+PAF+PostgreSQL cluster. They use STONITH based clusters, while I use 
quorum based clusters to survive a black out of whole datacenter. Using 
clusters without STONITH is forbidden in the RedHat documentation and is not 
recommended in the ClusterLabs documentation, that why I created this test bed 
to test such non-STONITH clusters. And I have a pretty tmux UI well suited for 
a presentation. :)

I glad to see that there is a concurrent project CTS. This is not bad, IMHO, 
they are complement each other in some way.

> # ra-tester:
> 
>  Damien Ciabrini from RH give a talk about ra-tester, which seems to extends
>  CTS with customs test, but I hadn't time to give it a look yet. Slides are
>  available here:
>  https://wiki.clusterlabs.org/wiki/File:CL2020-slides-Ciabrini-ra-tester.pdf

As I can see this is a python framework that will improve CTS somehow.

> Now, in regard with your multi-site clusters and how you deal with it using
> quorum, did you read the chapter about the Cluster Ticket Registry in 
> Pacemaker
> doc ? See:
> 
> https://clusterlabs.org/pacemaker/doc/en-US/Pacemaker/2.0/html/Pacemaker_Explained/ch15.html

Yep, I read the whole documentation two years ago. Yep, the ticket system was 
looked interesting at first glance, but I didn't see a method how to use it 
with PAF. :)

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