SUMMARY : Adding ptys to Solaris2.2

From: Tim Perala (
Date: Wed Sep 15 1993 - 21:49:53 CDT

On or about September 10, 1993 I posted to this list...

> What is the proper method of increasing the number of
> pseudo terminal devices (formerly ptys, now pts's) under
> Solaris2.2?
> I have looked high and low through the printed manuals,
> manual pages and everything in between. I found "mknod",
> which can create the individual device files in /devices/pseudo,
> and I suppose I could manually create the symlinks in /dev,
> but that all seems so crude. I could not get devlinks to
> create the links for me. I cannot find any configuration
> file anywhere that offers any clues either.
> I thought maybe boosting "maxusers" in /etc/system might
> ripple back and give me more pts following a "boot -r",
> but that was fantasy.
> We have 48 pts, and have run out!! I should be supporting
> 150+ users on this machine and I can't get more than about
> 40 logged in at one time because of this.

The solution is to add a line to the /etc/system file of the

        set pt_cnt=XXX

where XXX is the number of psuedo terminal devices you wish
to have created. Booting with the "boot -r" command will
them build the desired number of devices. Some respondents
also mentioned...

"You have to set the parameter 'npty' as well."
[I did not find this necessary to boost pt_cnt to 256. The
 documented default is 400.]

"Touch /reconfigure and reboot to force reconfiguration."
[This appears to have the same effect as "boot -r" from the
 monitor. Helpful if you are doing the work remotely!]

"There is a max of 255 pseudo terminals, 256 rolls over to 0."
[I did not find this to be the case. I created 256 but did not
 attempt any more.]

Many thanks to the honor-roll of respondents...

        Casper Dik <>
        Jared Rhine <> (Celeste Stokely) (Edsel Adap)
        Pat Cain (Denver) <pjc@denver.ssds.COM>
        Steve Chidlow <>
        murillo%ncsi@uunet.UU.NET (David Murillo)


Tim Perala ( (218) 726-6122 University of Minnesota, Duluth - Information Services (a tribute to a well-loved editor I once knew...) :wq

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