mailscanner (Solaris 2.6) Could not open file

Travis taz at AZTEK-ENG.COM
Tue Feb 10 13:54:08 GMT 2004


We had a problem with this, but the log said too many files open. Come to
find out that when Solaris 2.6
is installed by default it can only handle a maximum of 64 descriptors by 1
process at a time.  I added the following to /etc/system and rebooted the
machine and the problem cleared up:
set rlim_fd_cur = 1024
set rlim_fd_max = 1024
This sets both the hard and soft limits.  I find this just by doing a search
on the web on google for:
I know this is set high, but us it didn't break anything and was recommended
by one of the Sun Managers list.

----- Original Message -----
From: "Chang Kai Cheong" <kcchang at HKUSUA.HKU.HK>
To: <MAILSCANNER at JISCMAIL.AC.UK>
Sent: Monday, February 09, 2004 6:23 PM
Subject: Re: mailscanner (Solaris 2.6) Could not open file


> On Mon, 9 Feb 2004, Spicer, Kevin wrote:
>
> >
> > Its probably been tipped over the edge by the MyDoom virus.  IIRC these
limits
> > apply to processes and their children, so...
> >
> > 5 mailscanner processes * 100 message batches * 2 queue files per
message = 1000 files
> > Then we've got the output header files (another 500 files), then any
attachments/ bodies
> > being scanned (say 2 parts per message maybe another 1000).  And thats
before Spamassassin,
> > file command etc.etc.  Okay I admit that maybe all of these aren't open
at the same time -
> > but you can see how quickly they can be used up when the server is busy.
> >
> > The very fact that taking the messages out of the queue clears the
problem suggests it is a
> > symptom of the number of files involved.
> >
>
> Actually, I suspected it was file descriptor problem and hence I lowered
> the number of child from 10 to 5, max. message per scan from 100 to 80 and
> increase the file descriptors as my first step.
>
> However, I was confused by why MailScanner cannot restart successfully.
> The first (and subsequent) child process would get the "Cannot create +
> lock headers file" at retart of MailScanner.  I don't think the file
> descriptors would be used up immediately upon the restart of MailScanner
> (no message files should have been opened yet).
>
> I will try further up the number of file descriptor to observe whether the
> problem was still observed.
>
> Thanks,
> KC Chang



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