[CentOS] tinydns/djbdns opinion poll

Bill Campbell wrote:
>
>>> That sounds like the kiss of death for any critical service.  Can't it 
>>> figure out ahead of time that this is going to happen and let the 
>>> service keep running unchanged with a warning message about needing the 
>>> update instead?
>> You're missing the point.  If the service is already running, the
>> changes won't take effect until you restart the service with the new
>> binaries. And the whole patching exercise is what maintenance windows
>> are for, anyway.  Note that it's critical SERVICE, not critical SERVER.
>> The former is more important than the latter, so ideally you should be
>> able to take down the latter in order to upgrade one implementation of
>> the former.
> 
> I understand the distinction very well.  In the time we have been using
> this method, we have never taken down a service for any significant period
> of time (the services are restarted on installation by the RPM SPEC files'
> %pre, %post processing).
> 
> Of course we don't do things that are likely to take a critical service
> down without proper prior planning (often found out the hard way on our own
> systems :-).  If an update is likely to have an impact on operations, it is
> scheduled during a maintenance window.

In other words you'd dedicated sufficient human resources to undo 
whatever damage the package management system causes...

-- 
   Les Mikesell
    lesmikesell at gmail.com