[gentoo-dev] Re: Racing in init scripts

[Charlie C <phceac@yahoo.com>]

It is indeed a "very evil, very nasty thing" - as bugs like this tend to 
end up "WORKSFORME". Like #22421

In almost all cases, I suspect, the solution is a "--retry -TERM/60", or 
similar, in the "start-stop-daemon --stop" line....
This should probably be standard practice for all runscripts which use 
start-stop-daemon. My own preference is to explicitly specify the signal 
and timeout, but it can be simplified (... do the man thing!).

There are many, many, runscripts which (theoretically) will suffer from 
a race like this. One potential "show stopper" is sshd...I wonder if 
anyone has been locked out of a machine because of that one?
I tried, but was unable, to get "/etc/init.d/sshd restart" to fail - 
perhaps the problem only bites when the daemon or process in question 
has a trap for SIGTERM?

Anyway, for an example, please see 
http://bugs.gentoo.org/show_bug.cgi?id=31125 (from my own fair hand, 
this very morning), or indeed #29932 or 28345.

Having a rather slow (and overloaded) machine, I've probably seen these 
race conditions more than most.

Best wishes to all devs, and everyone else,

Charlie

-----------------
Eric Sammer wrote:
> While not exactly a "show stopper," I find that a number of the init 
> scripts (namely apache, bind, and maybe cyrus, IIRC) race too quickly 
> during a 'restart.'
> 



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