Strange disconnection pattern

[KenCunningham]

Good morning. I wonder whether anyone has experienced anything like the following: We have an M4000 with attached 5240 array. The box works fantasically well during main business hours, but, come 4:00 pm or so, will start to disconnect sessions on a regular (but not exact) basis.

This continues until about 8:30 the following morning. On Saturdays the disconnects continue all day, but do not occur at all on a Sunday. If I telnet to the box from one on a different subnet, I do not experience the disconnection behaviour at any time. Wierd! Does anyone have any clue what might be going on here before I lose the rest of my rapidly diminishing hair! If I can provide any further information, please let me know. Thanks.

Some days are diamonds, some days are rocks - make sure most are the former.

 

[KenCunningham]

I think I'll try monitoring with snoop - any experiences/recommendations in terms of interpreting the output grately appreciated! Thanks.

Some days are diamonds, some days are rocks - make sure most are the former.

 

[Annihilannic]

Are there any other patterns in the box's behaviour that match those time frames? CPU/memory usage? Scheduled jobs?

I'd be more inclined to think it was something else on the same network. Do you have any network traffic monitoring you can cross-reference with? Do you run backups over the same network?

Annihilannic.

 

[KenCunningham]

Hi Anni and thanks for your reply. Our network guys have been monitoring the network, but have yet to find anything significant. There are no jobs scheduled for these times, and backups are not run over the same network. I'll run with snoop and see what it says about the situation.

We might also try the other NIC in the box, although there is nothing in /var/adm/messages to indicate a problem. I'll keep you informed.

Some days are diamonds, some days are rocks - make sure most are the former.