HP -UX 10.20 - TELNET reached maximum limit.

[ALEXROC]

How increase the range ? Today I have only 64 telnet users. I need 256 minimum telnet sessions. Please anybody knows how fix this problem ? tks in advance.

[Ivan Krastev]

Change NPTY kernel parameter - http://docs.hp.com/en/939/KCParms/KCparam.Npty.html


regards,
ivan

[ALEXROC]

Ivan , tks for you answer. I will test this change and return soon. I´m afraid that the internal RAM memory will be insufficiency to put 120 telnet users. I´ll see...

[ALEXROC]

ps....: I have only 64 MB RAM on my system. I Will need 120 telnets (pseudo-tty)...Is only 64 MB support it ?

[Bill Hassell]

You can have dozens of users logon. However, the kernel parameters that need to be changed are:

npty
nstrpty
nstrtel

Set all of them to 256 (or 512 for future use (use SAM as it will create the required device files too). There is no limitation with RAM because HP-UX is a virtual memory system. That means that swap space will be used when there is not enough RAM. Since you are below the recommended minimum RAM for a 10.20 system, you are already using swap space (see the command: swapinfo -tam). If you have several gigabytes of swapspace, you should have no trouble with hundreds of users logging on.

HOWEVER: your system will be painfully slow since almost every task will require paging (swapping) things out and back in again. Adding more users will just make it slower and slower until you run out of swap space or run out of patience waiting for a login.

You need a minimum og 512 MB and preferably 1024 MB so the CPU can actually do work rather than waiting for paging to complete.

[Dennis Handly]

>Today I have only 64 telnet users. I need 256 minimum telnet sessions. ... I have only 64 MB RAM on my system.

What are all these users doing now and in the future?

[TTr]

After adding all these PTYs, you should consider adding more memory to your server. The 64MB may not be enough to support all these concurrent users. You should be able to find used memory for your server very easily. Do a search online.

[ALEXROC]

Ok everybody. Thanks a lot by your returns.
But until now I have same questions in doubt. When modify NPTY at SAM I have to modify NPROC and MaxUser too ?

[ALEXROC]

How many parameter have to be changed ?
NPTY
NSTRPTY
NSTRTEL
MAXUSER
NPROC

Is it ?
Now I have only 64 users that use telnet session running COBOL 4.0.
I will expand for 90 users work with telnet in same conditions.

[Bill Hassell]

ALEXROC wrote:
> How many parameter have to be changed ?
> NPTY
> NSTRPTY
> NSTRTEL
> MAXUSER
> NPROC

> Is it ?
Now I have only 64 users that use telnet session running COBOL 4.0.
> I will expand for 90 users work with telnet in same conditions.

Since you did not provide the current values for NPROC and NFILE, you can safely double the current values. MAXUSERS is actually hack to change several parameters at the same time. It works, sort of. But the values you need depend completely on what the users will need. Will they run many processes at the same time or just a simple menu program? I doubt that the users are running COBOL as this is a compiler which creates new programs. But even if all your users are writing new programs in the COBOL language, doubling the current values for NPROC and NFILE should be OK. Use the command:

sar -v 1

to see if proc or file values are nearing the maximum when the system is busy.