Defining the workgroup objectives

[a-aa]

Gerrit Pape wrote:

>On Sun, Jul 31, 2005 at 09:37:32PM +0200, a-aa wrote:
>  
>
>>I absolutly agree with that, but think about this.
>>If you have 5 services, all of which depends on the "master" being up. 
>>And that will try to connect to it's master at start.
>>
>>How do you deal with that?  A solution like this for all of them?:
>>
>>daemon --no-fork &
>>while ls <file that indicates it's up, or netcat to see if port is
>>open?>; do
>>  sleep 1
>>done
>>fg 1
>>
>>As executing them in order wont do anything.  You can't execute a daemon
>>with --no-fork and expect it to be up a millisecond after, then anything
>>depending on it has a high chance of failure.
>>    
>>
>
>The problem you're describing actually isn't a problem when using runit,
>you should try it out.
>
>On system boot all services are started up in parallel.  If services
>depending on other services fail if the services they depend on are
>not available, all is fine; due to the restart, they'll sort out
>automatically.
>
>For those special services that take a lot of resources before finding
>out that they should fail, you can add a minimal test for the
>dependency, but generally this shouldn't be necessary
>
> #!/bin/sh
> check-dependency || exit 1
> exec service-daemon
>
>This also may be a workaround for services that don't detect a missing
>service they depend on, but actually in this case the service daemon
>should be fixed to fail in this case.
>
>The advantage of this concept is that it not only works at boot-time,
>but also on system's uptime and services failing unintentionally.
>Furthermore in my opinion it's an quite easy solution to a rather
>complex problem; keep it simple stupid.
>  
>
hm, yeah, I suppose your right about that.

>Regards, Gerrit.
>  
>