mysql workbench failed to connect to server over ssh tunnel after server upgrade to ubuntu 16.04

Question

I had an active connection in MySQL Workbench to my Ubuntu 14.04 over ssh tunnel for last two years without any problem. But after Ubuntu upgrade to new 16.04 I keep receive following error:

13:41:56 [INF][     SSH tunnel]: Starting tunnel
13:41:56 [INF][     SSH tunnel]: Existing SSH tunnel not found, opening new one
13:42:03 [INF][     SSH tunnel]: Opening SSH tunnel to xxx.xxx.xxx.xxx:22
13:42:03 [INF][     SSH tunnel]: TunnelManager.wait_connection authentication error: Authentication error, unhandled exception caught in tunnel manager, please refer to logs for details
13:42:03 [ERR][     SSH tunnel]: Authentication error opening SSH tunnel: Authentication error, unhandled exception caught in tunnel manager, please refer to logs for details

Notes which may be useful:

1. I am able to connect over ssh tunnel by HeidiSQL.
2. I fail to establish connection by Navicat and keep getting SSH:expected key exchange group packet from server.

I read a lot to fix this issue some of suggestion are here:

• generate new ssh key on server,
• add KexAlgorithms to end of sshd_config,
• upgrade paramiko package of workbench Python.

I appreciate for any help you will provide.

Solution

After checking problem and trying to reproduce issues on other computers and those connected successfully. I found out some how the problem is caused by caching ssh known host.

I remove the folder under the user\application data\roaming\mysql\workbench\ssh\ but still problem remains.

For final try I uninstall MySql Workbench and delete setting folder mentioned before and install recently downloaded version of MySql workbench. Fortunately everything working fine.

Comments

[Grijesh Chauhan]

Thanks, the answer helped me. I downloaded WorkBenck for my version of Ubuntu. And I deleted the complete old workbench folder rm -rf ./.mysql/workbench, then installed the new workbench. It worked like charm