[comp.sys.apollo] Unattached gettys causing uncontrolled disk writing and buildup

weiner@novavax.UUCP (Bob Weiner) (06/06/89)

Just so no one else has to scratch his/her head over this one.  Apollo
says don't leave gettys turned on (look at /etc/ttys) on lines which
have no device attached under SR10.1.

I wanted to make it simple for people to attach terminals whenever they
wanted but generally not be able to modify the /etc/ttys file.  So I
started running a getty on each node's tty01 line.

Today, I found my disk being written to continually, immensely slowing
the performance of my DN4500.  No processes or users claimed to be
writing to the disk like that.  Apollo support said they had seen this
before.  I disabled the getty and rebooted.  The writing stopped and
about 30 megabytes of disk space immediately reappeared.
-- 
Bob Weiner, Motorola, Inc.,   USENET:  ...!gatech!uflorida!novavax!weiner
(407) 738-2087

steve@simon.UUCP (Steven E. Piette) (06/09/89)

In article <1337@novavax.uucp>, weiner@novavax.UUCP (Bob Weiner) writes:
> Just so no one else has to scratch his/her head over this one.  Apollo
> says don't leave gettys turned on (look at /etc/ttys) on lines which
> have no device attached under SR10.1.
> 
> I wanted to make it simple for people to attach terminals whenever they
> wanted but generally not be able to modify the /etc/ttys file.  So I
> started running a getty on each node's tty01 line.
> 
> Today, I found my disk being written to continually, immensely slowing
> the performance of my DN4500.  No processes or users claimed to be
> writing to the disk like that.  Apollo support said they had seen this
> before.  I disabled the getty and rebooted.  The writing stopped and
> about 30 megabytes of disk space immediately reappeared.
> -- 
> Bob Weiner, Motorola, Inc.,   USENET:  ...!gatech!uflorida!novavax!weiner
> (407) 738-2087

Bob,
You don't say if there is anything attached to the ports that are enabled.
 
If you have any length of cable attached to the serial port and nothing 
attached to the cable you can have a problem with noise being picked up
and the getty program entering a race tring to logon the noise.

With the proper lines entered into syslog.conf. You can log into syslog 
problems like this. They show up as invalid logins as fast as the system can
generate them. (maybe this is going on and that's where the 30MB went)

This is a fairly common problem and I seen it happen on lots of different
makes of systems.

Another place that would get written to by this type of problem is utmp and
wtmp. These would be truncated by a reboot giving the space back.

If your up for expermenting try letting it happen again and look at ps for
login's with junk user id's and those files filling up.



-- 
Steven E. Piette                              Applied Computer Technology Inc.
UUCP: {smarthost}!simon!steve                             1750 Riverwood Drive
INET: steve@simon.CHI.IL.US or spiette@SUN.COM             Algonquin, IL 60102
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