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SUMMARY : No of ports and Kernel parameters

The Question was
How to increase the no of ports on Ultra 450 running Solaris 2.6

The soln is

Eveyone gave same follow solution .

To increase the number of ptys (pseudo-terminal devices) under
Solaris 2.3, 2.4, and 2.5, four parameters must be added to (or
modified) in the /etc/system file:
set pt_cnt=<number desired>
set npty=<same number as pt_cnt>
set nautopush=<same number as pt_cnt>
set sadcnt=<2 * pt_cnt number>
Then do a reconfiguration reboot for the changes to take effect (e.g. boot -r
at the boot "OK" prompt).
For example to set to allowing 128 ptys:
set pt_cnt=128
set npty=128
set nautopush=128 (1 for every pty)
set sadcnt=256 (2 for every pty)
pt_cnt sets the number of pty's for System V, while npty sets the number
of pty's for BSD.
(USE 'boot -r' AT 'OK' PROMPT OR 'reboot -- -r' AT UNIX PROMPT)

For Second Question

> What other kernel parameters i should change to set
> Like 1) no of maximum processes
> 2) no of max processes per user
> 3) max no of ports per user

I got only following answer

Unlike SunOS, I don't think there are too many parameters to control
these. I think that Solaris computes the total process number limit
as 16 times the Mbytes of memory. The total number of process for
256Mb system is (16 * 256) = 4096. The limit of for user (non-root)
processes is 5 less (4091). Other than the root distinction, I don't
think there are any limits on a 'per-user' basis.

Michael gave the following two suggestions .
One of which is to change without reboot ,

First way is very simple but it requires system reboot.
1. add netxt line to /etc/system
    set pt_cnt=<amount of pts's> (without <> symbols)
2. issue the next command
    touch /reconfigure
2. reboot the system
    init 6

Second way is bit complex. It doesnt require system reboot.
1. start kernel debugger
    adb -k -w

2. issue the next command
    pt_cnt/W<amount of pts in hex format> (without <> symbols)

    for example: pt_cnt/W0x100 <- sets amount of pts's to 256 decimal
    NOTE: preserve the case of the letter W.

3. Press Ctrl+D to exit from kernel debugger

4. There are two special files for each pts in the system. You have to
    couple of files for each new added pts.

     The files are:

     First one is character special file in /devices/pseudo directory. The
     of the file looks like of the file looks like pts@0:<number of this pts> (without <> symbols).
It has
     minor equal to 24 and major equal of number of this pts.
     Second one is symbolic link in /dev/pts directory. It points to the
first file. The
     name of the file is equal to number of this pts.

     Here is an example for 45th pts:
     crw--w---- 1 root sys 24, 45 /devices/pseudo/crw--w---- 1 root sys 24, 45 /devices/pseudo/pts@0:45
     lrwxrwxrwx 1 root root /dev/pts/45 ->

     Here is a script for adding new pts. $1 is number of pts to be added.

    mknod $fname c 24 $cnt
    chgrp sys $fname
    chmod 644 $fname
    ln -s ../..$fname /dev/pts/$cnt
    chgrp root /dev/pts/$cnt

Once again Thanx for your help

Maheshwar Reddy