[Pacemaker] new RA: http_ping

[Dejan Muhamedagic]

On Fri, Aug 17, 2012 at 11:58:41AM +0000, Nicolai Langfeldt wrote:
> On 2012-08-16 15:01, Dejan Muhamedagic wrote:
> >> Didn't.  Looked at the ping/pingd and nginx RAs.  Grepped and googled a
> >> bit.  http-mon.sh isn't in the Ubuntu resource-agents 1:3.9.2-5ubuntu4.1
> >> package (as found ubuntu 12.04) and I never pulled from github.  Pulled
> >> together http_ping.
> > 
> > Well, if you're into development, the source repository is your
> > best friend :)
> 
> Watched and forked.
> 
> The http-mon.sh file seems to be rather incomplete and not very helpful
> from my point of view.

The code is several years old. It is used by the apache RA. It
would be excellent if you could offer some constructive critique.
Which part is incomplete? In which way do you find it unhelpful:
the implementation or the interface? Or something else?

> I can easily see how I could refactor my http_ping and cross it with the
> apache and nginx RAs to obtain a smaller code base with some common
> code.  Would you have a quick look at my http_ping RA and see if I'm
> roughly where I should be, or point me at docs that would make me able
> to get it there?

There is a RA development guide:
http://www.linux-ha.org/doc/dev-guides/ra-dev-guide.html

> To me, as it is a shell script, it seems pretty sane, but I've not
> actually read any best practices docs.

The point is really to reuse the existing code where possible.

> A idea that germinated a bit while I was doing http_ping was for a
> generic "monitor" agent that calls some simple stub scripts and only
> takes care of token and locking management itself.  I'd like it to be
> able to do http server and process watching.

Normally, one starts with the Dummy RA. Not sure what do you mean
by "token and locking management".

Cheers,

Dejan

P.S. Moving the discussion to the linux-ha-dev mailing list.
You'll need to subscribe over there to post.

> Nicolai
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