TCP hang?

[Dale Barnes]

Our network engineer is monitoring a problem for with a sniffer. The problem is that
a sqlnet connection with a remote sight dies regularly usually before 15 minutes, while
trying to extract information from the database. The network engineer has detected that in each case, a network packet with an invalid checksum is sent to the HP, the HP asks for a retransmit and shortly thereafter a retransmit of the packet is accomplished, but HP seems to go south (it does not respond). Any ideas?
I have contacted HP support and have installed the patches they asked for. The nic card is an HP-PB 100 Mb card. The OS is HP-UX 11.00.

[Berlene Herren]

Paul, maybe using the TCPDELAY option will help, if it is a telnet connection.

The following is an example of the
'telnetd' entry in /etc/inetd.conf:

telnet stream tcp nowait root /etc/telnetd telnetd -TCP_DELAY

LAN drivers are so fast, that when the default option (TCP_NODELAY)is set, the LAN drivers are immediately ready to process these tiny outbound packets. This negatively impacts performance where great numbers of small packets are bad.

Using TCP_DELAY, fewer packets with more data are sent. This slows down super-fast LAN drivers, making sure these drivers don't use up valuable LAN bandwidth.

Berlene

[Dale Barnes]

The connection is a sqlnet connection, not a telnet connection.

[Devbinder Singh Marway]

Just a thought, I am assuming your remote site is connected via routers , if so have you tried ,if possible a PC onto the local network (and setting up tnsnames) where your HP server is and see whether you get the same problem , because could it be the communication link from the remote site to your local site that is 'dodgy'hence packet corruption and timeouts.

[Paula J Frazer-Campbell]

Paul
Your problem might not be the HP machine,
as the connection is a remote one and the HP machine identifies the bad packet - requests a resend it appears to be behaving.
I would take a look at the network and as Davbinder suggests, drop the (router/bridge etc) out of the equation and connect locally to attempt the Sqlnet task.