Re: Automate backend registration

Hi Holger,

thanks for the answer. I already assemble HA-Proxy configuration with the help of Puppet. Now things require a bit more logic fe. I dont want to restart HA-Proxy if the config that ships with the RPM does not change. I'll definitely have a look at your script - thanks for the pointer.

CU,
Jens

On 03.08.2011, at 23:22, Holger Just wrote:

> Jens,
>
> Many people have a script that builds a working configuration file from
> various bits and pieces. As the actual needed configuration typically
> isn't something which follows a common path but depends on the
> environment and the actual applications and a thousand other bits, there
> isn't a standard here.
>
> But it really isn't hard to throw together a small shell/perl/python
> whatever script which concatenates the final config file from various
> pieces or uses some templating language of your chosen language.
>
> An script we use is https://github.com/finnlabs/haproxy. It consists of
> a python script which assembles the config file from a certain directory
> structure. This script is then called before a start/reload of the
> haproxy in the init script.
>
> So basically, you need to create your script for generating your Haproxy
> configuration, hook it into your init script and then, as a post-install
> in your RPMs put the configuration in place for your
> configuration-file-creating-script and reload Haproxy.
>
> To enable/disable previously registered backend components, you might be
> able to use the socket, but that usage is rather limited and mainly
> intended for maintenance, not for actual configuration changes.
>
> Hope that helps and sorry if that was a bit recursive :)
> Holger
>
> On 2011-08-03 22:52, Jens Bräuer wrote:

>> Hi Baptiste,
>> 
>> sorry for my wording. But you are right, with "registration" I mean
>> - add ACL
>> - add use_backend
>> - add backend section
>> so to sum it up "make haproxy aware of a new application".
>> 
>> There might be cases there I want to "only" add a server to existing backend, but that would be the second/third step.
>> The use-case is that I have HA-Proxy running and do a "yum/apt-get install" and the RPM should come with everything to integrate with HA-Proxy. I am sure that there must be some tool out there.. ;-)
>> 
>> Cheers,
>> Jens
>> 
>> 
>> On 03.08.2011, at 20:24, Baptiste wrote:
>>> Hi Jens,
>>> 
>>> What do you mean by "registration"?
>>> Is that "make haproxy aware of the freshly deployed application"  ?
>>> 
>>> cheers
>>> 
>>> On Wed, Aug 3, 2011 at 5:46 PM, Jens Bräuer <jens.braeuer#numberfour.eu> wrote:
>>>> Hi HA-Proxy guys,
>>>> 
>>>> I wonder whats the current state of the art to automate the registration of backend. My setup runs in on EC2 and I run HA-Proxy in front of local applications to easy administration. So a typical config file would be like this.
>>>> 
>>>> frontend http
>>>>   bind *:8080
>>>>   acl is-auth                         path_beg /auth
>>>>   acl is-core                         path_beg /core
>>>>   use_backend auth                            if is-auth
>>>>   use_backend core                            if is-core
>>>> 
>>>> backend auth
>>>>   server auth-1 localhost:7778 check
>>>> 
>>>> backend core
>>>>   server core-1 localhost:10000 check
>>>> 
>>>> All applications are installed via RPMs and I would like couple the installation with the backend registration. I like to do this as want to configure everything in one place (the RPM) and the number of installed applications may vary from host to host.
>>>> 
>>>> I'd really appreciate hint where I can find tools or whats the current state to handle this kind of task.
>>>> 
>>>> Cheers,
>>>> Jens
>>>> 
>>>> 
>>>> 
>> 
>>