FDDI problems

From: Tim W. Janes <janes_at_signal.dra.hmg.gb>
Date: Wed, 15 Nov 1995 22:10:35 +0000 (GMT)

Hello All,

I hope that as the majority of machines on our FDDI are alphas (and
all DEC) you consider that this question is appropiate to this list.

We have an FDDI loop that until 2 weeks ago consisting of

DecConcentrator 500 with 6 DecStation 500/2xx (via thin coax)
3COM Linkbuilder FDDI concentrator with 8 Alphas 3000/[46]00 (via UTP)
3COM Lanplex 2500 Ethernet switch with 8 Ethernets populated with more
Decstations & Alphas and PC's

Every couple of months we would be plagued with Ring Init messages
(10 - 100 per hour) - we were able to stop these by rebooting one or
more network items - we never really tracked down what cured the
problem but always could.

The weekend about 10 days ago we:-
a) Upgraded all alphas from OSF/1 3.0 to 3.2C
b) added to the FDDI network one 3000/600 as a sencond main NFS server
and 6 x 250 4/266

All went well for a week until on Friday we started getting MAC CRC
errors - just a trickle at first but by Sunday the whole system had
become unusable ( 5+ minutes hangs) and thousands of errors.

By Sunday evening all machines had logged approx 3000 MAC CRC errors
10,000 Ring Inits except the new 3000/600 NFS server which has logged
150,000 CRC errors and (>?) 65535 LEM events. ( all other machines
reported LEM events < 3 )

I took a gamble and rebooted this machine.

The MAC CRC error then fell back to a trickle which stayed until Monday
evening since then no errors at all.

So the questions:-

1) Anyone any idea what can possibly be happening here?

2) with 3.2C Ring Inits are no longer reported via syslog - are they
really so trivial that they can be safely ignored?

3) What is an LEM event? Does this indicate a hardware problem on the
only machine reporting these events?

4) Is the any way to reset the netstat -I fta0 -s counters?

5) More of a comment - but a reboot resets all counters to zero except
the seconds since last last zeroed field.

6) Can anyone recommend a good UK based FDDI expert to call in to try
to solve these problems?

I have appended the output of netsats -I fta0 -s on the 'rouge' machine
also extracts from the kernel logs on bothithe 'rouge' machine (joyce) and
our other main NFS server (byron) at the peak of the problem.

As always Many Thanks to this invaluable list.

Tim.

Tim Janes | e-mail : janes_at_signal.dra.hmg.gb
Defence Research Agency | tel : +44 684 894100
Malvern Worcs | fax : +44 684 894384
Gt Britain | #include <std/disclaim.h>


fta0 FDDI counters at Sun Nov 12 19:16:23 1995

       18437 seconds since last zeroed
  4294967295 ANSI MAC frame count
      142877 ANSI MAC frame error count
      242805 ANSI MAC frames lost count
  2574730150 bytes received
   183301359 bytes sent
    39574818 data blocks received
    46313618 data blocks sent
    58735038 multicast bytes received
      549875 multicast blocks received
      534261 multicast bytes sent
        5104 multicast blocks sent
           0 transmit underrun errors
           4 send failures
        5966 FCS check failures
           0 frame status errors
           0 frame alignment errors
           0 frame length errors
           0 unrecognized frames
           0 unrecognized multicast frames
           0 receive data overruns
           4 system buffers unavailable
           0 user buffers unavailable
        7607 ring reinitialization received
           0 ring reinitialization initiated
           1 ring beacon process initiated
           0 ring beacon process received
          20 duplicate tokens detected
           0 duplicate address test failures
           0 ring purger errors
           0 bridge strip errors
           0 traces initiated
           0 traces received
           2 LEM reject count
       65535 LEM events count
          18 LCT reject count
           0 TNE expired reject count
          54 Completed Connection count
           0 Elasticity Buffer Errors





Nov 12 17:44:17 byron vmunix: fta0: MAC CRC Error.
Nov 12 17:44:17 byron last message repeated 4 times
Nov 12 17:46:44 byron last message repeated 12 times
Nov 12 17:56:36 byron last message repeated 47 times
Nov 12 18:06:41 byron last message repeated 38 times
Nov 12 18:16:01 byron last message repeated 45 times
Nov 12 18:26:47 byron last message repeated 169 times
Nov 12 18:36:24 byron last message repeated 161 times
Nov 12 18:46:42 byron last message repeated 150 times
Nov 12 18:48:39 byron last message repeated 41 times
Nov 12 18:48:42 byron vmunix: fta0: E bit set
Nov 12 18:48:47 byron vmunix: fta0: MAC CRC Error.
Nov 12 18:49:19 byron last message repeated 11 times
Nov 12 18:51:04 byron last message repeated 41 times
Nov 12 19:01:12 byron last message repeated 135 times
Nov 12 19:07:35 byron last message repeated 41 times
Nov 12 19:07:47 byron vmunix: fta0: Duplicate token found
Nov 12 19:07:52 byron vmunix: fta0: MAC CRC Error.
Nov 12 19:08:24 byron last message repeated 12 times
Nov 12 19:10:25 byron last message repeated 21 times
Nov 12 19:20:26 byron last message repeated 208 times
Nov 12 19:28:45 byron last message repeated 4 times
Nov 12 19:40:23 byron last message repeated 2 times
Nov 12 19:48:26 byron last message repeated 46 times
Nov 12 19:48:30 byron vmunix: fta0: Link transmit failure
Nov 12 19:48:36 byron vmunix: fta0: MAC CRC Error.
Nov 12 19:49:07 byron last message repeated 13 times
Nov 12 19:51:04 byron last message repeated 30 times
Nov 12 19:55:30 byron last message repeated 18 times
Nov 12 19:55:38 byron vmunix: fta0: Duplicate token found
Nov 12 19:55:49 byron vmunix: fta0: MAC CRC Error.
Nov 12 19:55:55 byron vmunix: fta0: MAC CRC Error.
Nov 12 19:58:00 byron last message repeated 2 times
Nov 12 20:06:52 byron last message repeated 21 times


Nov 12 18:40:01 joyce vmunix: NFS3 server byron not responding still trying
Nov 12 18:40:02 joyce vmunix: fta0: MAC CRC Error.
Nov 12 18:40:06 joyce vmunix: NFS3 server byron ok
Nov 12 18:40:07 joyce vmunix: fta0: MAC CRC Error.
Nov 12 18:40:15 joyce vmunix: NFS3 server byron not responding still trying
Nov 12 18:40:16 joyce vmunix: NFS3 server byron ok
Nov 12 18:40:30 joyce vmunix: fta0: MAC CRC Error.
Nov 12 18:40:35 joyce vmunix: NFS3 server byron not responding still trying
Nov 12 18:40:36 joyce vmunix: NFS3 server byron ok
Nov 12 18:40:39 joyce vmunix: fta0: MAC CRC Error.
Nov 12 18:41:10 joyce last message repeated 5 times
Nov 12 18:42:05 joyce last message repeated 8 times
Nov 12 18:53:10 joyce last message repeated 17 times
Nov 12 18:57:20 joyce last message repeated 24 times
Nov 12 18:57:52 joyce vmunix: fta0: Block check error
Nov 12 18:57:52 joyce vmunix: fta0: Link confidence test failure inboth (local and remote) directions.
Nov 12 18:58:14 joyce vmunix: fta0: MAC CRC Error.
Nov 12 19:00:48 joyce vmunix: fta0: MAC CRC Error.
Nov 12 19:02:40 joyce last message repeated 10 times
Nov 12 19:11:15 joyce last message repeated 9 times
Nov 12 19:16:17 joyce last message repeated 2 times
Nov 12 19:29:44 joyce vmunix: fta0: MAC CRC Error.
Nov 12 19:46:07 joyce vmunix: fta0: MAC CRC Error.
Nov 12 19:54:14 joyce last message repeated 5 times
Nov 12 20:04:34 joyce vmunix: fta0: MAC CRC Error.
Nov 12 20:15:54 joyce last message repeated 10 times
Received on Thu Nov 16 1995 - 00:37:48 NZDT

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