We are experiencing some very strange problems which only seem to surface
with the ADSM Connect Agent for MS Exchange

We have three ADSM Servers.

Two of which are RS/6000 S7A's running AIX level 4.3.2 and ADSM 3.1.2.20

The other ADSM Server is an R40 running AIX level 4.2.1 and ADSM 3.1.15

We are using the ADSM Connect Agent for MS Exchange 1.1.0.0A (Fixtest A)

All of the servers have ATM cards using ATM Lan emulation software.

We are experiencing a lot of problems with TCP/IP failures with full backups
of the Exchange Servers using the ADSM Connect Agent.

On the two S7A's when we fire up about 3 or more full backup sessions
concurrently the Connect Agent sessions go into prolonged Recvw states until
eventually the sessions time out and the backups fails. This is typically
what happens. No errors are seen on the network or on the RS/6000.

Occassionally we see a scenario where the AIX server becomes 'dettached'
from the network. - it cannot be pinged, and we have observed ATM errors in
the aix error report on the Aix Servers. ADSM itself does not go down - it
just times out the sessions. Eventually the AIX server recovers from the ATM
errors and normal operation continues.
In this scenario errors have been observed on the ATM switch, however it
would appear that it is the RS/6000 which is letting go of the tcp/ip
connection.

We have checked our network for problems and have come up with nothing.
Futhermore this problem has only been observed with the Connect Agent itself
we have not been able to replicate this problem with standard BA client
sessions. We have had almost 50 BA client session running concurrently
without TCP/IP drops or errors.

What I have also noticed is that I can get a few more Connect Agent sessions
to run provided they are started up a few minutes apart. e.g. I start up a
session for one Connect Agent backup, then start another a minute after,
another a minute later..etc..

On the RS/6000 R-40 I see something completely different. I cannot get even
one Connect Agent backup to complete successfully. I have also observed a
'phantom' session appear on the ADSM Server during the backup where it
states that a node has received 4bytes of data - the nodename is blank.
Again no atm errros were found on the Aix server or on the ATM switch.

I'm particularly confused as to why we only see this problem with the ADSM
Connect Agent. We don't have any such problems with BA Client sessions.

Anyone any ideas?

Nathan








Nathan King
Open Systems Storage Management
*  (210) 913-5755
* Pager: 753-5755
* E-mail: nathan.king AT usaa DOT com

The opinions herein are mine and almost certainly do not reflect those of my
employer.