RISC Ultrix 3.1 NFS bug(?)

[Bill Mitchell]

I found that on a particular DECstation 3100, "setld -i" when redirected to
an NFS-mounted filesystem on a Sun-3/280 would produce a file with some null
characters in it.  The file would always have the right number of bytes, but
some bytes would be null.  The 3100 is a loaner and our DEC rep inquired about
this problem on some sort of DEC internal network.  He forwarded me a couple
of responses and they boiled down to "looks like a Sun bug".

I tried to reproduce the problem using another 3100 as a NFS server, but the
problem didn't appear.

I investigated further and found that "setld -i" has non-deterministic output:
the lines aren't always in the same order.  setld is actually a script and for
some reason it does a lot of echo's in the background.  I created a shell
script that does a bunch of echo's in the background (it follows at the
end of this message).  When run on a 3100 and redirected to an NFS filesystem
on another 3100, the observed failure rate is 100%.  When run on a Sun and
redirected to an NFS filesystem on a Sun or a 3100, the observed failure rate
is 0%.  So, it looks like some sort of client-side Ultrix NFS bug.

If you'd like to try to reproduce this on your system, here's the script:
-------------------------------------------------------------------------
echo '.xx xxx x'  &
echo '.xx xxxx'  &
echo 'xxx \- xxxxxxxxxxx xxx xxxxx xxxx'  &
echo '.xx xxxxxx'  &
echo '.x xxx'  &
echo '[\xx\-x\xx] [\xx\-x\xx] [\xx\-x\xx] [\xx\-x\xx] '  &
echo '[\xx\-x\xx\|] [\xx\-x\xx] [\xx\-x\xx] \xxxxxx...\xx'  &
echo '.xx'  &
echo '.xx xxxxxxxxxxx'  &
echo '.xxx "xxx xxxxxxx"'  &
echo '.xxx "xxxx" "xxxxxxxxxx"'  &
echo 'xxx'  &
echo '.xx xxx'  &
echo 'xxxxxxx xxxxx xxxx'  &
echo '.x xxxx'  &
echo 'xx xxxxxxxx xxx xxxxxxxx xx xx xxx xxxxxxxx xxxxxx.  xxxxxxxxx,'  &
echo 'xx xxxxxxx xxx xxxx xx xxx xxxxxxxx xxxxxx xxx xxxx:'  &
echo '.xx'  &
echo 'xxx xxxx'  &
echo '.xx'  &
echo 'xx xxxxxxxxxxx xxx xxxxx xxx xxxxx xxx xxxxxx'  &
echo 'xx xxx xxxxx xxx xxxx:'  &
echo '.xx'  &
echo 'xxx xxxxx xxxxn >xxxxn'  &
echo '.xx'  &
echo 'xx xx xxxxx xxxx xx xxxxx, xx xx xx xx xxxx (\-) xx xxxxxxxxxxx xx'  &
echo 'xx xxxxxxxx,'  &
echo '.xx xxx'  &
--------------------------------------------------------------------
Bill Mitchell				whm at sunquest.com
Sunquest Information Systems		sunquest!whm at arizona.edu
930 N. Finance Center Dr.               {arizona,uunet}!sunquest!whm
Tucson, AZ, 85710                       602-885-7700