topic Re: Query on SSH in Operating System - HP-UX

Query on SSH

Johnson Punniyalingam — Thu, 10 Dec 2009 10:40:06 GMT

what is the maximum number of connection we can have in SSH ?

I did check the man ssh_config file -> points to maximun 10

or it depends on number of pseudo devices

And how about the "batch jobs running" using SSH

does this also require me to increase pseudo devices

Re: Query on SSH

Michal Kapalka (mikap) — Thu, 10 Dec 2009 11:01:41 GMT

hi,

i thinks ists depend on you server if its enough powerfull and also if you have enough
pseudo devvices.

check this discusion :

http://www.unix.com/unix-advanced-expert-users/46982-max-numer-connections-per-sshd.html

mikap

Re: Query on SSH

dirk dierickx — Fri, 11 Dec 2009 07:44:46 GMT

i'm not aware of SSH having this limitation. if there is a limit at all, it will be whatever the OS limits.

Re: Query on SSH

Viktor Balogh — Fri, 11 Dec 2009 13:08:32 GMT

you can look for used pty's in glance -> press "t" for "system tables"

You can query the number of ptys from the kernel with kmtune like this: (in 11iv2/v3 look for the kctune command)

# kmtune -q npty
Parameter Current Dyn Planned Module Version
===============================================================================
npty 60 - 60

Re: Query on SSH

mvpel — Fri, 11 Dec 2009 14:06:40 GMT

The "MaxSessions" option in sshd_config is the maximum number of open sessions per network connection, not per system.

That option is tied to a feature in SSH 4.x and up called "connection multiplexing," which allows you to start additional SSH sessions over an existing TCP connection, via the use of a socket:

http://www.debian-administration.org/articles/290

The "MaxSessions" option was introduced in OpenSSH 5.1 to allow more fine-grained administrative control of the multiplexing feature.

Re: Query on SSH

Johnson Punniyalingam — Sat, 30 Jan 2010 06:33:42 GMT

Thanks to all, :)