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unfortunately ssh hangs up after login. Already uninstalled and installed it again. I can fix the issue temporary by erasing ~/.ssh and logoff and login on my system again.

Here is my ssh -v dump:

OpenSSH_5.8p1 Debian-7ubuntu1, OpenSSL 1.0.0e 6 Sep 2011
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to host [ip] port 22.
debug1: Connection established.
debug1: identity file /home/<user>/.ssh/id_rsa type -1
debug1: identity file /home/<user>/.ssh/id_rsa-cert type -1
debug1: identity file /home/<user>/.ssh/id_dsa type -1
debug1: identity file /home/<user>/.ssh/id_dsa-cert type -1
debug1: identity file /home/<user>/.ssh/id_ecdsa type -1
debug1: identity file /home/<user>/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.5p1 Debian-6
debug1: match: OpenSSH_5.5p1 Debian-6 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.8p1 Debian-7ubuntu1
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr 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
debug1: Server host key: <key>
debug1: Host 'host' is known and matches the RSA host key.
debug1: Found key in /home/<user>/.ssh/known_hosts:1
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Trying private key: /home/<user>/.ssh/id_rsa
debug1: Trying private key: /home/<user>/.ssh/id_dsa
debug1: Trying private key: /home/<user>/.ssh/id_ecdsa
debug1: Next authentication method: password
user@host's password:
debug1: Authentication succeeded (password).
Authenticated to host ([ip]:22).
debug1: channel 0: new [client-session]
debug1: Requesting
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LC_MESSAGES = de_DE.UTF-8
debug1: Sending env LC_COLLATE = de_DE.UTF-8
debug1: Sending env LANG = de_DE.UTF-8
debug1: Sending env LC_CTYPE = de_DE.UTF-8

Does anybody have a clue? 'cause I am clueless...

Thanks in advance

EDIT: Also I want to mention that the terminal seems to hangup completely because Ctrl + C or Ctrl + X don't work.

EDIT2: I also tried ssh -v host ls and the dump looks exactly the same except there is

debug1: Sending command: ls

at the end.

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up vote 1 down vote accepted

I finally found the problem - it was a corrupted wlan-router/dsl-modem combination. With new router and modem everythings works fine.

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Try to run strace ssh ... to determine what the system is doing when it seems to be hung.

(Please note that strace output contains your password, so do not post it without carefully editing out.)

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here comes the strace dump, unfortunately it was too long, so this is just the part after the login: – user28061 Oct 18 '11 at 15:50
The last line for me looks like select(7, [3 4], [], NULL, NULL) = 1 (in [3]) and then continues with a read, a select and finally with the login message. Could you check your /var/log/auth.log on your server, if there is any authentication failure? – lgarzo Oct 18 '11 at 16:18

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