“EOF on read” when using the SSH authentication method

Resolution for EOF on read error when using SSH authentication

This article is for Amanda Enterprise (AE).

Issue Symptoms

When using SSH as the authentication method, the following error is seen during a host check on the Backup| What page:

 WARNING: ultra2.zmanda.com: selfcheck request failed: EOF on read from ultra2.zmanda.com

To see more information, perform a host check from command line using the amcheck command. The below example shows running amcheck for the DailySet1 backup set: 

$ amcheck -c DailySet1

Amanda Backup Client Hosts Check
--------------------------------
Host key verification failed.

WARNING: ultra2.zmanda.com: selfcheck request failed: EOF on read from ultra2.zmanda.com
Client check: 1 host checked in 1.393 seconds, 1 problem found

Issue Descriptions

The authentication via SSH is failing. More detail can be seen in the amcheck output. In the sample output above, you can see that the SSH authentication is failing because
“Host key verification failed”. This particular message indicates an issue with the SSH keys failing to authenticate on the remote host. Another message you can encounter is
“Permission denied (publickey,gssapi-with-mic,password)” usually indicating that SSH public key authentication has not been set up at all. 

Resolution

Check the How to enable SSH authentication in Amanda Enterprise article for instructions on how to set up SSH public key authentication for the amandabackup user between
the backup server and client.

Once resolved, re-perform the amcheck above to confirm the issue is also resolved for Amanda.