Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rice!sun-spots-request
From: beirne@richsun.cpg.trs.reuter.com (Michael G. Beirne)
Newsgroups: comp.sys.sun
Subject: Ethernet bugs on Sun SPARC systems.
Keywords: Networks
Message-ID: <8507@brazos.Rice.edu>
Date: 4 Jun 90 16:49:35 GMT
Sender: root@rice.edu
Organization: Sun-Spots
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Approved: Sun-Spots@rice.edu
X-Sun-Spots-Digest: Volume 9, Issue 194, message 10

I have discovered two problems with the SPARC systems ethernet interfaces.

1. "spray localhost" loses about 10% of the packets sent. This doesn't
   sound bad until you realize that localhost packets don't leave the system
   and are just looped back in the kernel.

2. The SPARC systems can in certain circumstances put out bad ETHERNET
   packets with both the destination and SOURCE addresses wrong.

   Try this shell script:

    for i in `ypcat hosts|awk '{print $1}'`;do ping $1 3;done

   This will try to ping all the hosts in your NIS(yellow pages) hosts file.

   Then use "etherfind -x -n -greater 60 -o -less 90 >/tmp/badpackets" The
   bad packets have a type of 1F-00 which is unknown to Suns or anyone else
   for that matter.  This has been tried on a 4/110 running 4.0 and 4.0.1 and
   also on a SPARCstation 1 running 4.0.3c and 4.1.

   The first one would seem to mean that the SPARCstation is 10% artificially
   slower on the ethernet due to dropping packets. Does this mean that if
   this problem were fixed that NFS and telnet sessions would be 10% faster?
   The second problem seems more serious, and may be the cause of the 10%
   loss.

I reported the "spray localhost" problem last year and had hoped that it
would be fixed in 4.1 but no such luck. I put a call last week about the
second problem but SUN hasn't responded back yet.

Michael G. Beirne
beirne@richp1.UUCP or beirne@richsun.cpg.trs.reuter.com
or more reliably beirne@limerick.chi.il.us