Re: [gentoo-user] How to have init-scripts 'wait' for other servers

[J. Roeleveld]

On Friday 04 September 2009 11:23:09 Willie Wong wrote:
> On Fri, Sep 04, 2009 at 10:51:14AM +0200, Penguin Lover J. Roeleveld
squawked:
> > Does anyone know if an existing method to have init-scripts on server A
> > wait for a service on server B to be started?
>
> I have no idea if this would work or not. But have you tried writing a
> init script that does nothing but polls for the service and only
> exits when succeeds? Then you can edit the scripts for the dependent
> services to require it to start after your polling script.

I have been thinking of something similar, but before starting to write this 
myself, I wanted to double check if anyone has a better idea and/or already 
knows of a set of scripts/tools that already implement this.

> Something like: script /etc/init.d/foo polls tries for database
> connection. Inside it is a time-delayed loop that tries until it
> succeeds. Edit /etc/init.d/apache (assuming you are using it for your
> webserver) to 'need foo'

Or, obviously, fails if it doesn't come up within a certain (configurable) 
time.

> Again, I am just throwing this out randomly. Let me know if it works
> at all ;p

If there is no existing set of scripts, I will share whatever I come up with.

> Best of luck,

Thanks,

Joost