topic Re: No. of concurrent telnet sessions in Operating System - Linux

No. of concurrent telnet sessions

vasundhara — Fri, 02 Sep 2005 03:22:57 GMT

Hi,

Can you please let me know where can I find the number of concurrent telnet sessions that can be found on a linux server?

Certainly there would be a limit, but, how to find what is the limit? In which configuration file this will be present?

Thanks in advance for any information.

Regards,
VJ

Re: No. of concurrent telnet sessions

Muthukumar_5 — Fri, 02 Sep 2005 03:29:29 GMT

You can get telnet sessions as,

# ps -ef | grep 'telnet'

hth.

Re: No. of concurrent telnet sessions

vasundhara — Fri, 02 Sep 2005 03:43:44 GMT

This command gives the current no. of telnet sessions.

I want to know how many sessions are allowed

I mean....

If I keep on opening telnet sessions, at some point of time, I cannot open any more sessions until the previous ones are closed.

Where this limit will be present in the system? how can I find the limit?

Re: No. of concurrent telnet sessions

Alex Lavrov. — Fri, 02 Sep 2005 03:56:27 GMT

http://www.google.com/search?hl=en&q=linux+concurrent+telnet+sessions&spell=1

First link leads:

If you started with the original /etc/xinetd.d/telnet file, it should
look sort of like this after all the editing:

# default: on
# description: The telnet server serves telnet sessions; it uses \
# unencrypted username/password pairs for authentication.
service telnet
{
disable = no
instances = 100
flags = REUSE
socket_type = stream
wait = no
user = root
server = /usr/sbin/in.telnetd
log_on_failure =
log_on_success -= HOST

}

So, "instances = 100" <- is what are you looking for ...

Alex.

Re: No. of concurrent telnet sessions

vasundhara — Fri, 02 Sep 2005 04:15:09 GMT

I could not find this file at all. But, in inittab file it is written that:

# This is for the telnet session. The inetd does not limit
# number of sessions, but number of pty in /dev does.
t:2345:respawn:/sbin/mini-inetd -f -s telnet /sbin/telnetd telnetd -L /bin/login

So, there is some other parameter that is restricting no. of telnet sessions.

Re: No. of concurrent telnet sessions

Alex Lavrov. — Fri, 02 Sep 2005 04:24:53 GMT

Hmm ... what kind of linux you have?

Re: No. of concurrent telnet sessions

vasundhara — Fri, 02 Sep 2005 04:37:14 GMT

really sorry...
I am new to linux

How to find the answer for 'what kind of linux I have'????

Some other person installed the linux. So, Pl. let me know how to check what kind of linux it is.

Regards,
VJ

Re: No. of concurrent telnet sessions

Alex Lavrov. — Fri, 02 Sep 2005 04:43:59 GMT

Try:

cat /etc/issue

Re: No. of concurrent telnet sessions

Ranjith_5 — Fri, 02 Sep 2005 06:02:05 GMT

just start your web browser..for fresh installations it shows the linux home page.

Regards,
Syam

Re: No. of concurrent telnet sessions

Gopi Sekar — Fri, 02 Sep 2005 06:09:51 GMT

as what user you are trying to login as? if it is root then number of root logins via telnet is restricted by /etc/securetty file which states what are the consoles which are allowed for telnet connections for root.

check the 'man login' for more details on securetty file.

otherwise what is the error message you are getting when it is not allowing you to login?

Regards,
Gopi

Re: No. of concurrent telnet sessions

Procnus — Sat, 03 Sep 2005 17:37:27 GMT

You wrote before :
# This is for the telnet session. The inetd does not limit
# number of sessions, but number of pty in /dev does.
t:2345:respawn:/sbin/mini-inetd -f -s telnet /sbin/telnetd telnetd -L /bin/login

I would have a look at the number of /dev/pty* device files you have, e.g. ls /dev/pty* | wc -l

This may be the maximum number of concurrent telnet sessions that you are allowed. Once inetd runs out of available pty's no more telnet sesions can be created.

Cheers
Steven

Re: No. of concurrent telnet sessions

Ross Minkov — Tue, 06 Sep 2005 20:22:01 GMT

Let me guess, you are running Debian? The fact you have the mini-inetd. Check with:

cat /etc/debian_version

My recommendation -- use xinetd, don't bother with the mini-inetd.

-Ross

Re: No. of concurrent telnet sessions

vasundhara — Wed, 07 Sep 2005 02:57:31 GMT

None of the above give me the answer I am looking at.

I am not telling that you are wrong. May me the configuration of the server I am looking at is changed by the administrators.

Thanks a lot for the suggestions you have given.

Sorry that I am not allocating any points.

As I did not get the info I am looking for, I am not assigning points.

Re: No. of concurrent telnet sessions

Alex Lavrov. — Wed, 07 Sep 2005 03:08:43 GMT

Yes, but it's nice to thank the ppl that actually spent their time to help you, even if it didn't solve your problem. Don't you think?

Re: No. of concurrent telnet sessions

vasundhara — Wed, 07 Sep 2005 03:51:32 GMT

yep.
thats the reason I have told thanks and assigned 1point to all of you who spent your valuable time for me.

Regards,
VJ