ASE Cluster as Mail server - IMAP + NFS problem
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We have:
Digital UNIX V4.0F  (Rev. 1229)
TruCluster Software V1.6 (Rev. 227)
A two node ASE cluster ( Alphaservers 800 5/500 with 2Gb )
with /var/spool/mail on a shared RA 3000 (raid 5) as an ADVFS filesystem.
After running for about an hour the system hangs & a crash dump shows:
message buffer full of:
clntkudp_create: socket bind problem, 48pmap-kgetport: can't create RPC handler.
Network mail connectons are:
# grep imap crash-data.0 | wc -l
       490
# grep imsp crash-data.0 | wc -l
       100
# grep pop crash-data.0 | wc -l
        27
# grep exim crash-data.0 | wc -l
        10
imap is the ESYS/ExecMail (Simeon) version IMAP2bis Service 7.8(89isa) 
ESMTP Exim 3.02 #1
POP3 3.3(18) from UWash
Simeon IMSP 1.3 
Compaq suggest that the IMAP connections are taking all the ports available
to NFS ( which appears to be a hard wired kernel limit ) and this is then
hanging NFS.
Has anyone else seen similar problems - have a solution or suggestions ?
To workaround we are currently running IMAP on the host having the spool volume directly
mounted & avoiding the NFS mounted path with a link - but this breaks the
ASE rules for an NFS service & makes failover difficult. Our average IMAP
load is around 1000 connections.
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Kevin Worvill			phone : +44-1603-592392
IT and Computing Services 	fax   : +44-1603-593467
University of East Anglia	email : K.Worvill_at_uea.ac.uk
Norwich, NR4 7TJ, UK
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Received on Thu Oct 21 1999 - 11:30:43 NZDT