RUBIN@graf.poly.edu (David Rubin) (01/21/89)
We have just upgraded our two p4200's from 7.3a to the new 8.0 software,
and are experiencing delays in making Telnet connections.
Our configuration is as follows:
_______ _______
-----Eth 1-----| | | |
|p4200 a|------ 56 kB (COM-4) ------|p4200 b|-----Eth 3----
-----Eth 2-----|_______| |_______|
The delays occur when trying to reach a machine on a different Ethernet
(i.e. subnet) from the originator. If a connection has not recently
been made to the desired machine, the connection will take 20-30 seconds
to be established. However, any Telnet connections attempted to the same
machine shortly after the first attempt will experience no delay.
For example, if you Telnet to a machine, wait 20-30 seconds for the
connection to be made, then close the connection and Telnet again, there
is no delay. In any case, once the connection is made, there are no
delays.
We have not experienced any such problems running 7.3a. I assume there
are additional configuration parameters in 8.0 that might alleviate this
problem. We are running only TCP/IP, using RIP. Each interface is
defined in IP CONFIG as: Send net, subnet, static and default routes,
Override default routes.
I would appreciate any assistance on fixing this problem. Thanks...
David Rubin | INTERNET: RUBIN@graf.poly.edu
Polytechnic University | BITNET: RUBIN@POLYGRAF
Brooklyn, NY |CLIFF@UCBCMSA.BITNET (Cliff Frost {415} 642-5360) (01/21/89)
David,
It sounds like you are running into ARP cache timeouts.
The p4200 default is to timeout an ARP table entry after 5 minutes.
The p4200 won't deliver a packet if it has to ARP for the host: it
will drop the packet and do the ARP, relying on the end-to-end protocol
to retransmit the dropped packet.
The good news is that the ARP timeout values are configurable. ARP
is Protocol 3 in the p4200s.
Cliff