Applies to: SUSE LINUX 8.0-9.0
Symptom
After updating to OpenSSH version 3.7.1,it is no longer possible to login via PuTTY (a Windows SSH client). The file /var/log/messages contains the following (or a similar) message:
Nov 12 11:17:22 magnesium sshd[14522]: Failed password for root from ::ffff:192.168.0.5 port 1131
or
Nov 12 11:18:39 magnesium sshd[14539]: Received disconnect from ::ffff:192.168.0.5: 11:
No supported authentication methods available
The login process works without problems from a different Linux machine.
Cause
The password authentication has been switched off for the SSH service
whereas the PAM authentication and therewith the associated "ChallengeResponseAuthentication" (which is necessary for the latter) have been activated instead (see configuration file at /etc/ssh/sshd_config). The Challenge/Response mechanism is disabled in PuTTY's configuration for the protocol version 1 (default in PuTTY).
Solution
Set the protocol used by default by PuTTY to "version 2". The Challenge/Response mechanism is activated by default in PuTTY for this protocol. Select the menu options "Connection" -> "SSH" and change the "Preferred SSH protocol version" from "1" to "2". Make sure that the option "Attempt 'keyboard-interactive' authentication (SSH2)" in the submenu "Auth" is activated.
If you have to necessarily use the SSH protocol version 1, activate the option "Attempt TIS or CryptoCard authentication (SSH1)" in the same menu.
To save your settings on a permanent basis, select the menu item "Session" and press "Default Settings" first and then "Save".
A current PuTTY version is included in the directory dosutils/putty on the first SUSE Installation CD/DVD.
greetz und gute rutsch knallo
