unable to get ptys

[Umapathy S]

hi Experts


I am new into HPUX Administration, 10.2. I am getting errors like "Unable to get pty". My kernel paramter nstrpty is 60. I want to increase the number of available ptys. Please guide me through the steps I need to take besides increasing the nstrpty. Is there any relation with npty parameter regarding my above said error. Any info/links are greatly welcome. Thanks in advance.





regards


Umapathy S

[Steven Sim Kok Leong]

Hi,

Have you increased your npty yet?

Hope this helps. Regards.

Steven Sim Kok Leong
Brainbench MVP for Unix Admin
http://www.brainbench.com

[Umapathy S]

my nptr stands at 800 and it is more than enough. When the no of pts assigned crosses 60 I get the "unable to get pty" message.



regards

Umapathy

[Sanjay_6]

Hi,

Take a look at the threads below,

http://us-support3.external.hp.com/cki/bin/doc.pl/sid=e58a283c19b45bcfc8/screen=ckiDisplayDocument?docId=200000054497820

http://us-support3.external.hp.com/cki/bin/doc.pl/sid=e58a283c19b45bcfc8/screen=ckiDisplayDocument?docId=200000024613955

Hope this helps.

Regds

[Steven Sim Kok Leong]

Hi,

Use glance/gpm to verify your current running system table values under "System Table Report".

Hope this helps. Regards.

Steven Sim Kok Leong
Brainbench MVP for Unix Admin
http://www.brainbench.com

[Umapathy S]

hi Sanjay

thanks for your valuable links. The second link was really helpful. I tried the solutions as per the first link. But I got the same problem again. I hope the second link suits my problem as my system uses stream based ptys and I get the error whenever the number of users of pts cross 60 which is also the value of the parameter NSTRPTY.



My question is Is there any other commands I need to run after increasing NSTRPTY or it just works fine with only increasing the value and rebooting the machine.



thanks and regards

Umapathy S

[Umapathy S]

hi Sanjay


thanks for your valuable links. The second link was really helpful. I tried the solutions as per the first link. But I got the same problem again. I hope the second link suits my problem as my system uses stream based ptys and I get the error whenever the number of users of pts cross 60 which is also the value of the parameter NSTRPTY.





My question is Is there any other commands I need to run after increasing NSTRPTY or it just works fine with only increasing the value and rebooting the machine.





thanks and regards


Umapathy S

[Sanjay_6 · Accepted solution]

Hi,

Normally you should not be required to run any more commands after you have modified the kernel parameter, rebuilt the kernel and rebooted the system. However you can try and run "insf -e" after rebooting the system. This will manually create the device files including the pty files if they don't get created automatically.

Hope this helps.

Regds

[Sanjay_6]

Hi Uma,

You can give this link a try if your problem is still unresolved,

http://us-support3.external.hp.com/cki/bin/doc.pl/sid=b9cda57816b0cbff86/screen=ckiDisplayDocument?docId=200000027709246

Hope this helps.

Regds

[Bill Hassell]

npty and nstrpty are two different types of pty device files (that use different drivers. Early in 10.xx, few services would use the streams pty driver so nstrpty could remain low and npty high without problems. Withe recent patches to 10.20 and starting with 11.0, the majority of applications will use streams pty devices as the code is much more efficient.

So the recommendation is to use SAM to make your kernel changes and make npty = nstrpty. In doing so, SAM will also create the additional device files. If you don't use SAM, you'll have to use insf to create the device files by hand as you'll still get an error even after the kernel is changed. See man insf, specifcally options -e and -n.

[Umapathy S]

I was able to solve the problem. Thanks Sanjay, Bill and Steven for your valuable time and advice. I increased the NSTRPTY value to 600, rebuilt and rebooted the machine. It is now working nicely. Thanks again



regards

Umapathy S