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ssh doesn't work:::had to restart everytime

Hi all,

This is a strange problem on a RHEL5 box.
ssh stops working so not able to login to system
(even to console in ILO (HP server)).
Had restart the system then ssh works fine for a day or two
and again the problem starts.
Not sure what is wrong with this system.
Any help on this.

Following is the output when trying to ssh into it from another box and sits there forever

Code:

ssh -vvv  admin@linux1

OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008

debug1: Reading configuration data /etc/ssh/ssh_config

debug1: Applying options for *

debug2: ssh_connect: needpriv 0

debug1: Connecting to linux1 

debug1: Connection established.

debug1: permanently_set_uid: 0/0

debug1: identity file /root/.ssh/identity type -1

debug1: identity file /root/.ssh/id_rsa type -1

debug1: identity file /root/.ssh/id_dsa type -1

debug1: loaded 3 keys

Hello,

Have you tried backing up your sshd_config file, then starting from scratch with just the basic sshd config to rule out your config file? Also if you can, post your config file too.

Cheers,

Josh

Hi Josh,

I haven't changed sshd_config file after default install.

Below is the /etc/ssh/sshd_config file

Code:

more sshd_config

#      $OpenBSD: sshd_config,v 1.73 2005/12/06 22:38:28 reyk Exp $



# This is the sshd server system-wide configuration file.  See

# sshd_config(5) for more information.



# This sshd was compiled with PATH=/usr/local/bin:/bin:/usr/bin



# The strategy used for options in the default sshd_config shipped with

# OpenSSH is to specify options with their default value where

# possible, but leave them commented.  Uncommented options change a

# default value.



#Port 22

#Protocol 2,1

Protocol 2

#AddressFamily any

#ListenAddress 0.0.0.0

#ListenAddress ::



# HostKey for protocol version 1

#HostKey /etc/ssh/ssh_host_key

# HostKeys for protocol version 2

#HostKey /etc/ssh/ssh_host_rsa_key

#HostKey /etc/ssh/ssh_host_dsa_key



# Lifetime and size of ephemeral version 1 server key

#KeyRegenerationInterval 1h

#ServerKeyBits 768



# Logging

# obsoletes QuietMode and FascistLogging

#SyslogFacility AUTH

SyslogFacility AUTHPRIV

#LogLevel INFO



# Authentication:



#LoginGraceTime 2m

#PermitRootLogin yes

#StrictModes yes

#MaxAuthTries 6



#RSAAuthentication yes

#PubkeyAuthentication yes

#AuthorizedKeysFile    .ssh/authorized_keys



# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts

#RhostsRSAAuthentication no

# similar for protocol version 2

#HostbasedAuthentication no

# Change to yes if you don't trust ~/.ssh/known_hosts for

# RhostsRSAAuthentication and HostbasedAuthentication

#IgnoreUserKnownHosts no

# Don't read the user's ~/.rhosts and ~/.shosts files

#IgnoreRhosts yes



# To disable tunneled clear text passwords, change to no here!

#PasswordAuthentication yes

#PermitEmptyPasswords no

PasswordAuthentication yes



# Change to no to disable s/key passwords

#ChallengeResponseAuthentication yes

ChallengeResponseAuthentication no



# Kerberos options

#KerberosAuthentication no

#KerberosOrLocalPasswd yes

#KerberosTicketCleanup yes

#KerberosGetAFSToken no



# GSSAPI options

#GSSAPIAuthentication no

GSSAPIAuthentication yes

#GSSAPICleanupCredentials yes

GSSAPICleanupCredentials yes



# Set this to 'yes' to enable PAM authentication, account processing,

# and session processing. If this is enabled, PAM authentication will

# be allowed through the ChallengeResponseAuthentication mechanism.

# Depending on your PAM configuration, this may bypass the setting of

# PasswordAuthentication, PermitEmptyPasswords, and

# "PermitRootLogin without-password". If you just want the PAM account and

# session checks to run without PAM authentication, then enable this but set

# ChallengeResponseAuthentication=no

#UsePAM no

UsePAM yes



# Accept locale-related environment variables

AcceptEnv LANG LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES

AcceptEnv LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT

AcceptEnv LC_IDENTIFICATION LC_ALL

#AllowTcpForwarding yes

#GatewayPorts no

#X11Forwarding no

X11Forwarding yes

#X11DisplayOffset 10

#X11UseLocalhost yes

#PrintMotd yes

#PrintLastLog yes

#TCPKeepAlive yes

#UseLogin no

#UsePrivilegeSeparation yes

#PermitUserEnvironment no

#Compression delayed

#ClientAliveInterval 0

#ClientAliveCountMax 3

#ShowPatchLevel no

#UseDNS yes

#PidFile /var/run/sshd.pid

#MaxStartups 10

#PermitTunnel no

#ChrootDirectory none



# no default banner path

#Banner /some/path



# override default of no subsystems

Subsystem      sftp    /usr/libexec/openssh/sftp-server

Have you made sure that you are using the latest version of sshd for your distro?

How to verify that...

below are the ssh related packages installed.
How to check if i have latest package installed ?

Code:

 rpm -qa |grep ssh

openssh-server-4.3p2-72.el5

openssh-clients-4.3p2-72.el5

openssh-askpass-4.3p2-72.el5

openssh-4.3p2-72.el5

By looking at that, you should be good. Have you tried doing a general reinstall of ssh? Just trying to rule out the simple stuff before you get too deep into this :p

No i haven't tried a reinstall of ssh.
i am not sure if that solves the problem.
Even if it solves, i want to know what causing this problem.

Quote:

Originally Posted by linuxandtsm (Post 4431898)

No i haven't tried a reinstall of ssh.
i am not sure if that solves the problem.
Even if it solves, i want to know what causing this problem.

Me too; I was just asking a general question. I even searched around for a while and didn't come up with anything too thrilling to help. Maybe someone else has some input? Honestly, this problem has never happened to me either....