rlogind: Out of ptys

[girishb]

We have Open Suse Enterprise Linux installed on the server which was working like charm!!

We now not able to rlogin, telnet, or ssh it is giving below error messages...

rlogind: Out of ptys.
rlogin: connection closed.

Connected to server1.
Escape character is '^]'.
telnetd: All network ports in use.
Connection closed by foreign host.

ssh_exchange_identification: Connection closed by remote host

Any idea whats going on!!

Thanks
Girish

[Kapil Jha]

Well I have not worked on Suse,but still can you check ps -ef|Grep telnet
as it says all ports are in use.
do you have ptys entry in securetty(if it exist in linux).
Hope this help.
BR,
Kapil

[Stuart Browne]

Weird. How many connections have you got? Also, which version of OSE?

In the older 2.4 serires of kernels, there was an upper limit as defined in the kernel configuration when compiled (see CONFIG_UNIX98_PTY_COUNT), but under the newer 2.6 series of kernels, it's fully dynamic (as far as I'm aware).

In any case, most distro's would have the limit up around the 2048 mark (or 256 at the very least).

So, how many logins are you expecting?

[Stuart Browne]

Oops, I'm wrong.

Check '/proc/sys/kernel/pty/max'. Also check what '/proc/sys/kernel/pty/nr'. This should be how many pty's are currently assigned.

[girishb]

Thanks to Everyone!!

Stuart,
Here is the output:
server1:~ # cat /proc/sys/kernel/pty/max
4096
server1:~ # cat /proc/sys/kernel/pty/nr
10

Usually we have around 80 users connecting to this server daily.

The issue was resolved after performing server reboot.

Ideally we did not wanted to reboot the server; but had to do it. We are still looking for the cause of the issue.

/var/log/messages reveals:

Dec 17 10:52:52 server1 res: pam_resmgr: tty is NULL
Dec 17 10:52:55 server1 -23: pam_resmgr: tty is NULL
Dec 17 10:52:56 server1 -23: pam_resmgr: tty is NULL
Dec 17 10:53:06 server1 su: (to nobody) root on none
Dec 17 10:53:06 server1 -23: pam_resmgr: tty is NULL
Dec 17 10:53:12 server1 su: (to nobody) root on none
Dec 17 10:53:18 server1 -23: pam_resmgr: tty is NULL
Dec 17 10:53:24 server1 -23: pam_resmgr: tty is NULL
Dec 17 10:53:26 server1 -23: pam_resmgr: tty is NULL

Any idea why!!

Thanks,
Girish

[Stuart Browne]

pam_resmgr.. That's a module for pam I've not seen before.

I'm guessing that you've got a small limit defined in '/etc/resmgr.conf' which is being used in the authentication process, limiting the number of simultaneous logins for a given user class or some such.