TELNET Session lock up

TELNET Session lock up

Post by Brendan Rega » Sat, 24 Jul 1999 04:00:00



I am trying to troubleshoot a problem we are having with users at a remote
site.  They are accessing our Sun Server running UNIX System V release 4.
They are running telnet sessions from Win98 workstations.  They are
accessing our site via a 56k frame relay connection.  They are accessing a
UniVerse database.
    The problem they are having is that their Telnet sessions are locking
up.  We do not have this problem with any other remote sites.  We have
checked the routing tables in both routers and they appear to be fine.
Also, the Hosts file on the UNIX machine appears to be correct.
    I am not very familiar with UNIX.  Does anyone have any ideas what might
be causing this sort of problem or how to troubleshoot it?  Any suggestions
would be greatly appreciated.

Brendan

 
 
 

TELNET Session lock up

Post by Jeffrey Bouli » Sun, 15 Aug 1999 04:00:00




>I am trying to troubleshoot a problem we are having with users at a remote
>site.  They are accessing our Sun Server running UNIX System V release 4.
>They are running telnet sessions from Win98 workstations.  They are
>accessing our site via a 56k frame relay connection.  They are accessing a
>UniVerse database.
>    The problem they are having is that their Telnet sessions are locking
>up.  We do not have this problem with any other remote sites.  We have
>checked the routing tables in both routers and they appear to be fine.
>Also, the Hosts file on the UNIX machine appears to be correct.
>    I am not very familiar with UNIX.  Does anyone have any ideas what might
>be causing this sort of problem or how to troubleshoot it?  Any suggestions
>would be greatly appreciated.

A silly question, but could they be in the habit of pressing control-s?
That is a "stop" character, which will freeze the terminal. Pressing
control-q would unstick it.

Also, when their telnets lock up, are you able to ping their windows '95
computers from the Sun, and can they ping the Sun from their windows
boxes? These are not equivalent tasks...

Do all of them lock up at once, or do only one or two of them have
problems at one time?

Have you installed the latest patch cluster from sunsolve.sun.com?

                        Yours Truly,
                        Jeff Boulier

 
 
 

TELNET Session lock up

Post by Rich Bente » Sat, 21 Aug 1999 04:00:00





> >I am trying to troubleshoot a problem we are having with users at a remote
> >site.  They are accessing our Sun Server running UNIX System V release 4.
> >They are running telnet sessions from Win98 workstations.  They are
> >accessing our site via a 56k frame relay connection.  They are accessing a
> >UniVerse database.
> >    The problem they are having is that their Telnet sessions are locking
> >up.  We do not have this problem with any other remote sites.  We have
> >checked the routing tables in both routers and they appear to be fine.
> >Also, the Hosts file on the UNIX machine appears to be correct.
> >    I am not very familiar with UNIX.  Does anyone have any ideas what might
> >be causing this sort of problem or how to troubleshoot it?  Any suggestions
> >would be greatly appreciated.

> A silly question, but could they be in the habit of pressing control-s?
> That is a "stop" character, which will freeze the terminal. Pressing
> control-q would unstick it.

> Also, when their telnets lock up, are you able to ping their windows '95
> computers from the Sun, and can they ping the Sun from their windows
> boxes? These are not equivalent tasks...

> Do all of them lock up at once, or do only one or two of them have
> problems at one time?

> Have you installed the latest patch cluster from sunsolve.sun.com?

>                         Yours Truly,
>                         Jeff Boulier

Without any more details it could be alot of things. One problem, especially in
dealing with
data bases is the mtu (maximum transmission unit) size that is going across your

frame relay. It it's too large, like well over 1500 or if it's going across a
WAN say-things
are going to slow way down. This is because telnet usually consists of small
buffered commands
as opposed to data base large buffered requirements. Hope I was some help;-)

 
 
 

1. Lock User Account in Solaris 2.6 after 3 failed telnet sessions

Hi Bill,

You can create /var/adm/loginlog with permissions 0600. If the login failed
it is logged in this file after 'n' wrong user-IDs/passwords (n=5 per
default, you may change this with RETRIES=x in /etc/default/login to x). You
can write a script to parse /var/adm/loginlog. Notice that this behaviour
you try to implement can be used for a DoS attack and is not restricted to
telnet. Your users should use ssh anyway to prevent package sniffer attacks.

Hope this helps.

Frank

2. Hayes ESP enhanced mode drivers available (alpha)

3. SCO OSE 5.0.2 LS command Locks any telnet session.

4. Man Pages (additional)

5. Lock User Account in Solaris 2.6 after 3 failed telnet sessions

6. PLS RECOMMEND PARTITIONS

7. Control-C and Telnet -- locking up my session

8. CDROM Unrecognized

9. Telnet sessions locking up over ppp?

10. Can I lock a telnet session to defined pseudo tty ?

11. Lock User Account in Solaris 2.6 after 3 failed telnet sessions

12. Lock ups with SCO and Caps lock

13. Session disconnects in a telnet session