topic Re: unable to get pty in hp - ux in Operating System - HP-UX

unable to get pty in hp - ux

Tushar_hiwase — Mon, 20 Aug 2012 08:20:31 GMT

Hi,

i am getting "unable to get pty" error while logging to the hpux server using vnc. I get this error only for non root users during vnc session (with gui).

It has 11.31 OS version.

Do i need to change any kernel setting ?

thanks in advance

regards,

tushar

Re: unable to get pty in HP-UX

Dennis Handly — Mon, 20 Aug 2012 08:40:33 GMT

Have you looked at npty(5)? I'm not sure if kcusage will tell you how close you are?

Re: unable to get pty in HP-UX

Tushar_hiwase — Mon, 20 Aug 2012 09:42:00 GMT

Hi Dennis,

Please see below findings.

[3] % kctune |grep -i npty
npty 1000 1000
[4] % kcusage |grep -i npty
npty 0 / 1000
[5] %

Re: unable to get pty in HP-UX

leewilliam99 — Mon, 20 Aug 2012 12:23:27 GMT

There are actually 3 types of pty (pseudo terminal device files). Be sure to adjust nstrpty and nstrtel as well as npty. Rather than try to analyze which type of conection is being used, just make all 3 = 1000. You can use SAM so that the device files will be automatically created. Unfortunately, SMH dropped this very useful feature, so after adjusting the parameters to 1000, be sure to run insf to create the device files:

insf -e -n 1000 -p 1000 -s 1000

Re: unable to get pty in HP-UX

Tushar_hiwase — Mon, 20 Aug 2012 12:39:39 GMT

Hi leewilliam99,

As per you have suggested, i have set the entries of nspty,nstrpty and nstrtel to 1000. And while executing the command given by you for creating the device files, i got below error.

[5] % insf -e -n 1000 -p 1000 -s 1000
insf: Invalid range for autochanger cartridges -- 1000
usage: insf [-d driver | -C class] [-H hw_path] [-I instance] [-D dir] [-q|-v]
[-e] [-n npty] [-s nstrpty]
usage: insf [-v] -L
[6] %

Re: unable to get pty in HP-UX

leewilliam99 — Mon, 20 Aug 2012 13:40:21 GMT

Oops, drop the -p option.

insf -e -n 1000 -s 1000

Re: unable to get pty in HP-UX

Tushar_hiwase — Mon, 20 Aug 2012 13:48:14 GMT

still no luck...getting same error messages for non root user..

# kctune |grep -i npty
npty 1000 1000
# kctune |grep -i nstrpty
nstrpty 1000 1000
# kctune |grep -i nstrtel
nstrtel 1000 1000
# insf -e -n 1000 -s 1000
insf: Installing special files for pseudo driver ptym
insf: Installing special files for pseudo driver ptys
#

Re: unable to get pty in HP-UX

Dennis Handly — Mon, 20 Aug 2012 19:11:00 GMT

>getting same error messages for non root user.

Did you check the kcusage of the nstrpty and nstrtel to see if you need more than 1000?

Re: unable to get pty in HP-UX

Tushar_hiwase — Tue, 21 Aug 2012 06:49:34 GMT

Hi Dennis,

Below are the kusage for npty, nstrpty and nstrtel.

[6] % kcusage |grep npty
npty                        0 / 1000
[7] % kcusage |grep nstrpty
nstrpty                     1 / 1000
[8] % kcusage |grep nstrtel
nstrtel                     0 / 1000
[9] %

Do i need to increase kcusage also using sam ?

Re: unable to get pty in HP-UX

Dennis Handly — Tue, 21 Aug 2012 07:10:34 GMT

>Do I need to increase kcusage also using sam?

As leewilliam99 said, that would be easier if you were on 11.23.

But it does seem strange that you have "no" usage but you get that error.

Re: unable to get pty in HP-UX

Tushar_hiwase — Tue, 21 Aug 2012 07:30:19 GMT

Hi Denis,

So is there any workaround or setting other than this i have to do on my 11.31 machine ?

otherwise do i need to do reinstallation of hpux on my server ?

Re: unable to get pty in HP-UX

Dennis Handly — Tue, 21 Aug 2012 07:49:52 GMT

>So is there any workaround or setting other than this I have to do on my 11.31 machine?

Try increasing all 3 to 2000?

>do I need to do reinstallation of HP-UX on my server?

I doubt it. What you need is tusc output of VNC so you can see exactly what type of PTY error it was getting.

Also, I'm not sure why the root permissions matter. Is there a weird pty with bogus permissions?

Re: unable to get pty in HP-UX

Tushar_hiwase — Tue, 21 Aug 2012 08:13:20 GMT

denis,

Increased the all 3 kctune values to 2000.

still no luck.....

Below are the vnc session logs. Hope you will get something from here.

Tue Aug 21 13:16:58 2012
Connections: closed: x.x.x.x::52549 (Clean disconnection)
SMsgWriter: framebuffer updates 29
SMsgWriter:    copyRect rects 5, bytes 80
SMsgWriter:    hextile rects 171, bytes 238260
SMsgWriter:    ZRLE rects 2, bytes 12690
SMsgWriter:    raw bytes equivalent 3452450, compression ratio 13.757521

Tue Aug 21 13:18:02 2012
Connections: accepted: x.x.x.x::52552
SConnection: Client needs protocol version 3.8
SConnection: Client requests security type VncAuth(2)

Tue Aug 21 13:18:06 2012
VNCSConnST: Server default pixel format depth 16 (16bpp) big-endian rgb565
VNCSConnST: Client pixel format depth 8 (8bpp) rgb max 3,3,3 shift 4,2,0
VNCSConnST: Client pixel format depth 16 (16bpp) little-endian rgb565

Tue Aug 21 13:19:35 2012
XserverDesktop: Added unknown keysym 0xffeb to keycode 255

Note. : Where x.x.x.x is my ip address which is intentionaly removed.

Also attaching the vnc session screenshot of my normal user.

Re: unable to get pty in hp - ux

rariasn — Tue, 21 Aug 2012 10:05:58 GMT

Hi Tushar:

Verify owner and file permission:

# ll -d /dev/pty

user: bin Group

drwxr-xr-x 2 bin bin 8192 Mar 25 2010 /dev/pty

# ll /dev/pty

User: bin Group: tty

crw-rw-rw-   2 bin        tty         17 0x000000 Mar 25 2010 ttyp0
crw--w----   2 ran        tty         17 0x000001 Aug 21 12:00 ttyp1 <-- user ran connected
crw-rw-rw-   2 root       root        17 0x000002 Sep 2 2011 ttyp2 <-- user root connected
crw-rw-rw-   2 bin        tty         17 0x000003 Mar 25 2010 ttyp3
crw-rw-rw-   2 bin        tty         17 0x000004 Mar 25 2010 ttyp4

...

rgs

Re: unable to get pty in hp - ux

Tushar_hiwase — Thu, 23 Aug 2012 06:39:36 GMT

thanks rariasn...

it worked for me...

Re: unable to get pty in hp - ux

Nivin — Wed, 03 Jul 2013 08:16:06 GMT

My system states.

# pwd
/
# kcusage |grep npty
npty                        2 / 60
# kcusage |grep nstrpty
nstrpty                   120 / 120
# kcusage |grep nstrtel
nstrtel                     0 / 60

# ll -d /dev/pty
drwxr-xr-x 2 bin bin 2048 Mar 6 10:38 /dev/pty

# ll /dev/pty

total 0
crw-rw-rw-   2 bin        tty         17 0x000000 Nov 22 2006 ttyp0
crw--w----   2 scaldera   tty         17 0x000001 Jul 2 12:13 ttyp1
crw--w----   2 alcatel    tty         17 0x000002 Jul 3 10:14 ttyp2
crw-rw-rw-   2 bin        tty         17 0x000003 Mar 6 12:08 ttyp3

what do i need to do next to fix this issue?

Please advise

Re: unable to get pty in hp - ux

Robert_Jewell — Wed, 03 Jul 2013 15:29:35 GMT

> nstrpty 120 / 120

Looks like you need to increase this tunable as described by the posts above.

Use 'kcweb' to start the kernel configuration utility. As described above, change each value and then use the 'insf' command to reset the device files.

-Bob