Here is how we resolved this - it is a "feature" of linux...


# cat /etc/host.conf
#
# /etc/host.conf - resolver configuration file
#
# Please read the manual page host.conf(5) for more information.
#
#
# The following option is only used by binaries linked against
# libc4 or libc5. This line should be in sync with the "hosts"
# option in /etc/nsswitch.conf.
#
order bind, hosts
#
# The following options are used by the resolver library:
#
multi on
mdns off


The resolution to your issue is the "multi on" and "mdns off".

------------------------------

Message: 3
Date: Sun, 20 Mar 2011 22:46:26 -0700
From: Crowey <netbackup-forum AT backupcentral DOT com>
Subject: [Veritas-bu]  NetBackup Not Using Backup NIC
To: VERITAS-BU AT MAILMAN.ENG.AUBURN DOT EDU
Message-ID: <1300686385.m2f.351626 AT www.backupcentral DOT com>

Gidday, with respect to ...

The REQUIRED_INTERFACE option in bp.conf/registry might be what you are after

and ...

Both NICs are on the same IP segment.
addr:172.20.10.23 Mask:255.255.255.0
addr:172.20.10.24 Mask:255.255.255.0
As far as the OS is concerned they are on the same dedicated segments with 
equal weight (Metric:1) in the routing table and probably binding to eth0 
first. Run bpclntcmd -self to see which interface(s) NBU thinks it is using. My 
guess is both will show up.
REQUIRED_INTERFACE only works for outbound TCP SYN requests sent from the 
server. If you are backing up using both interfaces then REQUIRED_INTERFACE is 
not an option. If only using the eth2 then try this-
REQUIRED_INTERFACE = server-backup.
Otherwise to try using static host routes to force the OS to pick eth2 over 
eth0 depending on which IP segment the clients are on if you want your backups 
to use that interface.

I already have REQUIRED_INTERFACE set to the correct DNS name (server-backup).

When I ran bpclntcmd -self I got ...

yp_get_default_domain failed: (12) Local domain name not set
NIS does not seem to be running: (1) Request arguments bad
gethostname() returned: gandalf-backup
host server-backup: server-backup.mf.com.au at 172.20.1.44
aliases:     server-backup.mf.com.au     server-backup     172.20.1.44

You can see that for time being at least, I've put the secondary (eth2) NIC 
onto another subnet to see if that improves performance (it doesn't seem to 
have helped much - but that's a different problem!) - but I had gotten exactly 
same response before I'd changed IP/VLAN.

Cheers
John

+----------------------------------------------------------------------
|This was sent by jcrowe AT marketforce.com DOT au via Backup Central.
|Forward SPAM to abuse AT backupcentral DOT com.
+----------------------------------------------------------------------


_______________________________________________
Veritas-bu maillist  -  Veritas-bu AT mailman.eng.auburn DOT edu
http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu