Server abandons client sessions..is that normal?

[droach]

Running an older TSM server running v6.3.5. Most every client on this server has a MAXNUMMP set to 2. My CommTimeOut is set to 900. Have been running like this for a couple years and have not seen any issues...until now.

Have a Windows 10 client running a backup over a VPN connection and it is constantly failing due to exceeding the mount point limit of 2. I bumped it to 10 for this one client and have been watching it to see what is going on. I setup a continuous ping between the client and the TSM server and started the backup (over the VPN connection).

Noticed that if I drop even 1 ping the current session between the server and the client is abandoned and a new session is initiated. Every time there is the smallest interruption in communications between the two the session gets abandoned and a new session is started. Sometimes I don't even lose a ping and this happens.

So, my question is, is this normal or should the client and server try to resume using the existing session? I know I could reduce the COMMTIMEOUT to help kill the abandoned sessions faster, but it was set this high years ago on a recommendation from IBM. With this current situation I need pristine network conditions for backups to keep from failing due to exceeding their MAXNUMMP.

 

[marclant]

I know I could reduce the COMMTIMEOUT to help kill the abandoned sessions faster, but it was set this high years ago on a recommendation from IBM.

The recommendation is the default, unless there's a special case you are trying to address. I suspect that's what happened when 900 was recommended. Connections normally get dropped in milliseconds, sometimes seconds, so there is usually not a need to have the commtimeout set for several minutes.

It's normal to not reuse the session. If the connection is dropped, the session gets cancelled and a new one is started.

Does the node have KEEPMP set to YES or NO? If it's YES, you should consider no.

 

[droach]

I tried manipulating the KEEPMP and it did not seem to help. It was set to NO. I tried setting it to YES, but have since set it back to NO.