Thanks to everyone who responded with their suggestions. As a couple people
(szgyula_at_tarkus.pha.jhu.edu and curt_at_vphos.net) advised, the problem turned out
to be full-duplex vs. half-duplex configuration. I'm not sure how to check the
current setting, but running ifconfig tu1 speed=200 solved the problem. The
configuration must have gotten screwed up with the switches bouncing up and
down during the firmware upgrades. Interestingly, the configuration was not
corrected this morning when I rebooted the systems; I'm going to add the
speed=200 line to rc.config for the future.
Thanks again, and happy hacking!
Jon Friesen
MY ORIGINAL MESSAGE:
>Greetings,
>
>We're experiencing an intractable network wierdness:
>
>We have 5 alphas and ~200 PCs on a switched ethernet network (using BayStack
>28115 and 350T switches). This configuration has worked great up until a
week
>ago. Now (after adding some more switches and upgrading some switch
firmware)
>we are experiencing a strange phenomenon:
>
> transferring data (eg an FTP session) from an Alpha to a PC yields between
>2-10 K/sec, or occasionally hangs completely
> transferring data from the PC to the Alpha transfers at normal speed,
e.g. 100
>- 500 K/sec
>
>This cause of this phenomenon has been narrowed down to the Alphas---we've
>reproduced the problem when only two alphas were connected to the switch,
and
>nothing else. My hypothesis is that we are seeing some incompatibility
between
>the alphas and the latest switch firmware --- has anyone else had any
>experience with conflicts between BayStack switches and alphas? What kernel
>parameters can I play with involving the ethernet card (a DEC 100baseT card,
>device tu1)---e.g. frame type, fragmentation parameters, etc. Are these
>documented anywhere?
>
>Sadly, I am not an ethernet guru, nor even a DEC whiz (I'm an AIXer,
sigh), so
>don't be afraid to insult my intelligence with your answers :)
>
>Thanks in advance!
>Jon Friesen
Received on Fri Jan 23 1998 - 21:11:46 NZDT