Ian, Sorry for the confusion. Yes, auto_dev is a simple indirect map. Since it is a negative lookup, the entry we are looking up doesn't exist in the auto_dev map, so I didn't bother showing any of its contents.
So for some reason it appears that negative caching does not work for the example I previous described since there is one lookup for every "cd /home/dev/example", not one lookup for every negative timeout seconds. - Mike On Thu, Nov 13, 2008 at 9:08 PM, Ian Kent <[EMAIL PROTECTED]> wrote: > On Mon, 2008-11-03 at 10:03 -0500, Mike K wrote: > > Hello, > > > > Based on what I have found, autofs5 supports caching negative lookups, > > but it doesn't appear to be working for me. Although my understanding > > of how it is supposed to work is very limited, so I may just be > > mistaken. > > > > My client system: Red Hat 5.2, autofs-5.0.1-0.rc2.88.x86_64, > > kernel-2.6.18-92.el5.x86_64, with automounter maps in a NIS+ server > > (client in niscompat mode). > > NFS Server: A popular NAS appliance > > > > auto_master snippet: > > /home/dev auto_dev > > Is this meant to convey meaningful information? > Is auto_dev a simple indirect map? > > > > > By default (and a recommended setting), the NAS appliance requires > > that all mounts from uid 0 come from a reserved port (0-1024) on the > > client. On our client system, repeated yp lookups for entries which > > don't exist will consume all ports in 0-1024, causing other legit > > mount attempts to fail since they are denied by the NAS appliance. > > This does not happen on Red Hat 4 or 3 systems. > > > > Reproducer: 'while true; do cd /home/dev/example; done'. "watch -n 1 > > 'netstat -an | grep TIME_WAIT | wc -l'" will show the number of > > sockets in TIME_WAIT increase rapidly. > > > > In this case, each 'cd /home/dev/example' causes a yp lookup for a > > directory that doesn't exist in the NIS table, consuming a socket and > > leaving it in TIME_WAIT for 60 seconds. > > > > Is this situation supposed to be prevented with caching negative > > lookups? > > If auto_dev is a simple indirect map there should be one lookup every > negative timeout seconds. > > > > > Thanks, > > Mike > > _______________________________________________ > > autofs mailing list > > autofs@linux.kernel.org > > http://linux.kernel.org/mailman/listinfo/autofs > >
_______________________________________________ autofs mailing list autofs@linux.kernel.org http://linux.kernel.org/mailman/listinfo/autofs
