Jason Harrell (
Mon, 02 Feb 1998 15:48:52 -0600

Well... I checked my /etc/system file for those two parameters "pt_cnt"
and "npty" and they were both set to 96 which is more than enough for
our little shop. To "fix" the problem I ended up rebooting but w/o the
"-r". I did a "ps -aef | grep -c shelltool* prior to reboot and there
were 30 shelltools open. But then I realized that in addition to those
shelltools there are rsh and telnet sessions and etc. So, I'm going to
increase the "pt_cnt" and "npty" to 200 for now. I'll monitor things
over the next few weeks to try to find an ideal setting for our shop.

THANKS!!! to everyone who responded :)

Below are some of the various solutions that were sent to me:

"Ku, Eddie" <

You either have a lot of stale KEEPALIVE sessions or you need to bump up
your max_client count.

More info is needed for exact command invocation to fix this

FreakaZoid <>

Increase your psuedo terminals. Or reboot the machine and teach users
to log out properly.


I had this problem once & I had increased the no. of psuedo terminals &
it worked fine.The changes were made in /etc/systems.

The entries are

set pt_cnt=255
set npty=512

Do a boot -r & see if that helped.


Chenthil Kumar 


Igor Kolker <>

It usualy mean you have use up all you tty's. Solaris by default has only ~43 tty's (pts). You have to add 2 lines to /etc/system and reboot to reconfigure your /de and /devices directories. The line you add are: set pt_cnt = ### set npty = ### I have used numbers a big as 600 without problems, but dont set it to more than you need.


Sean Ward <>

Hi Jason. You've run out of tty's. Here's the solution from the Solaris 2 FAQ:

3.39) How can I have more than 48 pseudo-ttys? Edit /etc/system and add the following line: * System V pseudo terminals set pt_cnt = <num> Halt the system and boot -r. You can essentially have as many as you like, but you'll probably run into some other limit somewhere. More than 3000 are supported. In the unlikely event that you run out of BSD-style ptys, you can increase them as well. The maximum here is currently 176 for pty[p-z][0-9a-f]. This is somewhat less that the BSD maximum of 256 limited by 8 bit device minor numbers. BSD ttys are awkward to use and all programs I found support SYSV ptys without trouble. * You don't need this. Increasing this value too much usually * just wastes memory. * BSD application never support more than 256 ptys. * Solaris 2.x supports no more that 176 BSD ptys. set npty = <num> But you're not there yet, you also need to edit /etc/iu.ap and substitute the new value of "npty-1" for the "47" on the following line, in case you do increase the number of BSD style ptys. ptsl 0 47 ldterm ttcompat Halt the system and boot -r.

The latest Solaris 2 FAQ, including an HTML version, and some other goodies can be obtained through ftp from <>.