topic maxusers in Operating System - HP-UX

maxusers

Jeffrey F. Goldsmith — Fri, 13 Jun 2008 21:08:39 GMT

I have an rp3440-4 w/ HP-UX 11.23. On Tuesday two of my users contacted me reporting that they could not connect to the UNIX server. The error that they were getting was:
“telnetd: Telnet device drivers missing: No such device”.
I tried to login to the server and received the same error. When I checked how many users were logged in I found that there were 60 users currently logged in.
How do I increase the number of users that are allowed to logon to my server at one time?

Re: maxusers

Kenan Erdey — Fri, 13 Jun 2008 21:54:45 GMT

Hi,

first from sam or cli you can increase npty,
nstrpty and nstrtel kernel parameters to the value you desired. But this process requires reboot because of recompiling kernel. after setting max values you can create device files by:

rm /dev/pts/*
rm /dev/pty/*
cd /dev
insf -e
insf -d telm
insf -d tels

Hope it helps.
Kenan.

Re: maxusers

Avinash20 — Sat, 14 Jun 2008 03:28:04 GMT

There might be an issue with orphans telnet connection which are not getting closed.
If you feel that the number of users have incresed, then
# sam -> Tuning Kernel Parameters -> "nstrtel"
to increase the configured nstrtel number. There should be at least as many nstrtel entries as the maximum number of xterm sessions plus further allowance for any
other inbound telnet connections.

Re: maxusers

Rasheed Tamton — Sat, 14 Jun 2008 11:33:35 GMT

kctune|egrep 'npty|nstrpty|nstrtel'

Increase the above 3 kernel parameters to at least 200.

kctune -v npty nstrpty nstrtel|grep Change

You will have to reboot the system after changing the above.

Change the values through SAM or kcweb. SAM would be more easier.

rgds.

Re: maxusers

TTr — Sat, 14 Jun 2008 12:15:52 GMT

1. Check the 3 psudo tty parameters as indicated above. Use the "kcweb -t" command to look and change the parameters. (This is what sam is using too)

2. Since you have to reboot the server to increase 3 tty parameters, take a look at some more parameters. With that many users on your server chances are you will hit limits on other parameters in the near future. Candidates are maxfiles, maxfiles_lim, maxuprc, nfile, nflocks, ninode, nproc
Use glance (if you have it) and sar to find the current usage

3. If you are still having problems check if you have the latest patches, "Mux and PTY", "tlenet kernel" etc.

Re: maxusers

Asif Sharif — Sat, 14 Jun 2008 16:20:43 GMT

If you have any session with root user then do these,

# cd /
# rm /dev/pty/*
# rm /dev/pts/*
# insf -e
# cd /dev
# insf -d telm
# insf -d tels

else login with single user mode and do the above.

http://forums11.itrc.hp.com/service/forums/questionanswer.do?admit=109447626+1213463847929+28353475&threadId=988543

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=195265

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=753678

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=134283

Regards,
Asif Sharif

Re: maxusers

Jeffrey F. Goldsmith — Wed, 18 Jun 2008 21:35:32 GMT

After reading everyones responses I know what I need to change. I have made the changes to my server, increasing npty, nstrpty and nstrtel kernel parameters to the value 200 each. Then I received an e-mail from the manager of Application Support which said that they wanted the three kernel parameters increased to 500 each. Is this a reasonable request or will it create a problem with system resources?

Re: maxusers

Hein van den Heuvel — Wed, 18 Jun 2008 21:50:12 GMT

500 in not very much, but if the system was happy with 60 then 200 is a fine next value.
Sounds like the application managers are trying to cover up for slacking earlier.
fwiw,
Hein.