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
