SIM 5.3 Reporting False Lost Comms

[Mathew Haynes]

G'day,

First time poster so unfortunately I will be asking for help rather than giving it.

We run HP SIM 5.3 with SP1 on top of a Server 2003 standard SP2 - DL380 G5. It has not been configured very well, it was basically set up and left to discover it's own devices with no extra tools running. I plan on going through and getting it up to spec but I'm very new to SIM.

Anyway, the problem comes from 2 devices which are sitting in a remote site but still on the LAN. These 2 devices are sitting in a small building connected via a 802.11g link with a high gain antenna. An ID card reader is linked back to a server in our datacenter through these devices.

The wireless g link is very reliable for a wireless connection.

HP SIM is reporting these 2 devices every hour or so as having lost comms with them - which from my tests is not true. Constant pinging works fine and the tag reader served by these devices does not drop any requests, aside from the standard <1% allowance.

After 10 minutes of lost comm's, HP SIM regains comm's and clears the event. It is set to ping 5 times with a timeout of 5 seconds. I believe it is also set to use SNMP with 1 try and a 5 second timeout. The SNMP settings are left as defaults on the devices in question.

Note that ICMP packets sent from a cmd.exe window on the HP SIM server work fine when SIM is reporting lost comms.

Also, the 2 devices do not always go offline according to SIM at the same time, it can be any combination of device A, B or both.

Is there anyway to find out more info why SIM thinks it's lost comms?

Any thoughts?

Cheers for any help you can provide,
Matt