Getting error message "rlogind: Unable to allocate pty on remote host."

[senthil_kumar_1]

Hi All,

I have K580 server running HP-UX 10.20.

I used to login through rlogin. It was working fine.

But suddenly, Today I am not able to connect the server through rlogin.

I am getting below given error message while try to connet through rlogin.

Example:


#rlogin serverA

rlogind: Unable to allocate pty on remote host.
Connection closed.


My Questions:

1)Why I am not able to connect the server through rlogin?

2)Will it be resolved if I go for reboot of the server?

3)How to resolve the issue?

It is very urgent.

[Pete Randall · Accepted solution]

All the pty's on your remote host are in use. You need to allocate more by increasing the value of npty in your kernel. Of course this requires building a new kernel and re-booting. If this can't be done immediately then you might be able to kill of some of the processes occupying pty's on the remote server.
A reboot of the server would also free up the pty's but I would suggest increasing the kernel parameter "npty" before re-booting.


Pete

[Pete Randall]

Sorry for the repeated posting, but I should have mentioned that you can use glance on the remote server to see how many pty's are in use:

gpm > reports > system info > system tables report


Pete

[senthil_kumar_1]

Hi All,

My current setting:


Name Current Pending
Value Value
npty 200 200
nstrpty 200 200


What is the maximum value we can set. There is 4GB of RAM installed.

[Pete Randall]

The maximum value is limited only be the memory available. However, keep in mind that raising the value only increases the size of the kernel minimally - like a few Kb at most. If I were you, I would at least double the current value.


Pete

[Steven E. Protter]

Shalom,

After Pete's steps it is necessary to run the following command.

insf -e

This will create terminal files and psuedo files needed for sessions.

SEP

[senthil_kumar_1]

Hi All,

Therefore we have to follow below steps:

1)Increase the kernel parameter "npty"

2)Run #insf -e

3)reboot the server.

[Dennis Handly]

Your previous thread for background:
http://forums.itrc.hp.com/service/forums/questionanswer.do?threadId=1427311