RP7420 vPar connectivity issue

[pside15]

Basically, we have a rp7420 with one nPar that is split into two vPars. The server can talk to everything on the network just fine but then it randomly looses communication with 2 specific servers but can still talk to everything else on the network just fine. Then the connection with the 2 servers comes back up with no changes made at all. Below is a more detailed description. I'm not working directly with these machines but I've been asked to help figure out what the issue is. I'm strictly a hardware engineer and my software knowledge is limited so I'm trying to get any help at all. This is our first time using a vPar system and could be overlooking something in the network configuration that is different from running them in out usual nPar config. I'm not connected to these machines but can get any information from them that is needed.

We have 1- RP7420 running hpux 11.31   that intermittently loses connection to an RP74xx (app server) and a BL8xx (db server).... and then connection is restored after a while and no changes by either the network or unix team.  

That being said, while we lose connection to those servers from isupplier, we are able to ping other servers on the network from isupplier.....

Below is updated information after some troubleshooting steps were taken to rule out a hardware issue.

Latest update

Yesterday, we had a network connection run that went straight from the RP74xx to the Cisco (managed) switch, took the Dell PowerConnect unmanaged switch out of play.
The switch port is set to 1000FD, not auto negotiate

I tried a different NIC on the server, moved it from LAN1 to LAN2 (completely different card), it is set to 1000FD, as we were having connection issues with LAN1
NIC is showing no error (inbound or outbound)
memory and cpu utilization are low as nothing is running on this server yet.

Ping to database server is fine for a while and then we lose connection.

Database server is a BL870c i2.
The NIC on it is set to 1000FD
lanadmin is showing no errors on the NIC (inbound or outbound)
Memory and cpu utilization are low during the issue.

While connectivity between these 2 servers is lost, they both can ping other servers on the network.

When we first moved to the new switch and the new NIC on the RP74xx server yesterday, we were able to get good results on file copy (about 16/ms) and that lasted for a number of hours and then connectivity was lost.  I checked it this morning and the connectivity between the 2 servers is intermittent

[pside15]

Ok, just wanted to post an update.

The server has been booted as a nPar and is still experencing the same connectivity issues.

If we do a netstop and then a netstart right afterwards it is fine for about 30 minutes and then the issue starts again.

Does anyone have any idea as to what the issue might be?