SSh disconnecting very frequently

[Ivan Krastev]

Make sure, that ssh server is running.

ps -ef | grep sshd

and start it:
/sbin/init.d/secsh start

regards,
ivan

[Grayh]

I see that ssh is already running...

# ps -ef | grep sshd
root 24563 5894 0 08:39:54 ? 0:00 sshd: root@pts/0
root 24678 24596 0 08:44:24 pts/0 0:00 grep sshd
root 5894 1 0 16:33:53 ? 0:00 /opt/ssh/sbin/sshd

Here are some more errors found ...

sshd[5894]: Server listening on :: port 22.
sshd[5894]: Server listening on 0.0.0.0 port 22.
sshd[5904]: error: Bind to port 22 on :: failed: Address already in use.
sshd[5904]: error: Bind to port 22 on 0.0.0.0 failed: Address already in use.

sshd[5904]: fatal: Cannot bind any address.


I also see many debugs when i issue the below command

# ssh -v hpbox01
OpenSSH_5.1p1+sftpfilecontrol-v1.2-hpn13v5, OpenSSL 0.9.7m 23 Feb 2007
HP-UX Secure Shell-A.05.10.007, HP-UX Secure Shell version
debug1: Reading configuration data /opt/ssh/etc/ssh_config
debug1: Connecting to hpbox01 [10.3.20.23] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/3
debug1: identity file /.ssh/identity type -1
debug1: identity file /.ssh/id_rsa type -1
debug1: identity file /.ssh/id_dsa type -1
debug1: Remote protocol version 1.99, remote software version OpenSSH_5.1p1+sftp
filecontrol-v1.2-hpn13v5
debug1: match: OpenSSH_5.1p1+sftpfilecontrol-v1.2-hpn13v5 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.1p1+sftpfilecontrol-v1.2-hpn13v5
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: AUTH STATE IS 0
debug1: REQUESTED ENC.NAME is 'aes128-cbc'
debug1: kex: server->client aes128-cbc hmac-md5 none
debug1: REQUESTED ENC.NAME is 'aes128-cbc'
debug1: kex: client->server aes128-cbc hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
The authenticity of host 'hpbox01 (10.3.20.23)' can't be established.
RSA key fingerprint is 90:a8:40:29:74:aa:17:43:b0:df:f4:a7:59:3b:b2:5e.
Are you sure you want to continue connecting (yes/no)? y
Please type 'yes' or 'no': yes
Warning: Permanently added 'hpbox01,10.3.20.23' (RSA) to the list of known hosts.
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password,keyboard-interacti
ve
debug1: Next authentication method: publickey
debug1: Trying private key: /.ssh/identity
debug1: Trying private key: /.ssh/id_rsa
debug1: Trying private key: /.ssh/id_dsa
debug1: Next authentication method: keyboard-interactive
Password:

[vz7r1x]

My cent on your problem...

Please stop or kill all the processes which are listending on port 22 and restart sshd process.

kill -9 xxxx

Thanks

[G V R Shankar · Accepted solution]

Hi,
If you have already done the following, please ignore it.

There could be a dupluicate IP in the n/w. Please run the following commads

ll /var/adm/nettl*

I assume that /var/adm/nettl.LOG000 has the latest timestamp

netfmt -F -t 15
/var/adm/nettl.LOG000

You would know if there is duplicate IP

Cheers,
Ravi.

[Tingli]

Maybe some other processes are using port 22. Use netstat to check about it.

[Grayh]

Thanks Every One