Same tty

[Leah Chow]

Hello,

I have a question needs someone to help me.

When a user tries to log into glovia ERP system (stay on HP 11.00 server), they get stuck at the start up screen with the below message:

Stack for terminal in use by another process.

Then the user will be locked.

We asked Glovia about this problem, here is their answer:

'You have run away processor(s) that is using up the tty. When someone logged in with the same tty, you will get this error message. You might want to recycle the server to clear up the run away processors....'

How should I do it? Does it actually means it is time to install new patches for telnet on server?

[Romen Q. Cordial_1 · Accepted solution]

Hi Leah,

I had that problem before becasue of Openssh, even do the user already logout and exit the user id and the tty he used still log on the system when you do who. while the application doesn't know if the tty is free to use or still have process thats why application allocate same tty. Definitely you have run away process.

1. type who -a, who -T or w = try to identify which one is runaway, ps -ef|grep 'userid' if no process found either of one of those same tty user id, that one is considered run away process, the only temporary workaround that I would suggest to you to see the correct output from 'who' command is:
1. # cat /dev/null > /etc/utmp
2. You may want to trim /etc/wtmp too if you want:
# cat /dev/null > /etc/wtmp and or /etc/btmp.

NOTE: System reboot will even make the system cleaner.

Hope this will help you,
Regards,
Romen Q. Cordial

[Sunil Sharma_1]

Hi,

When a user log into server it get one tty assign to it and when he logout that tty should get free. This is not happening in your case. Power recycle of your system is a temperory solution of this . becuase all tty get freed once you power recycle. You can try to increase npty parameter in kernel.

You have to find out why tty is not getting release when user log out. user may not be exiting in proper way he might be just closing window insted of using exit command.

Sunil

[Leah Chow]

Thank you guys, I tried who -a or who -T, found out there have bunch of run away processes on my server.

Is there anyway I can prevent run away processes? If there are any patches available, could you tell me the patches ID?

Thanks
Leah

[Romen Q. Cordial_1]

Hi Leah,

Some points will be good if you think it help you my suggesstion. Check this web site http://www.darkwing.com/idled/ Another thing is check the what cause why of runaway like my side the reason is the old version or Openssh we're using, perhaps you look on this issue. Patch is another thing, normally every user if not transactions OS will kick them out within period of time.

Regards,
Romen