Issue sftp backup extension - delete known_hosts?

[Martin_Sauer]

Server operating system version

Red Hat Enterprise Linux release 8.7 (Ootpa)

Plesk version and microupdate number

Plesk Obsidian Version 18.0.51.1

Plesk Obsidian Version 18.0.51.1
OS Red Hat Enterprise Linux release 8.7 (Ootpa)
Extension SFTP backup Storage Extension

Since the switch to a new backup-Server the sftp-backup no longer works:
Transport error: Extension transport: ext://sftp-backup/server/: Failed to list the directory "" at host.domain.TLD: unable to make SSH connection: ssh: handshake failed: ssh: unable to authenticate, attempted methods [none publickey], no supported methods remain

Presumably ssh does not work due to the known_hosts entry. Because the server fingerprint changed with the switch to the new server.

Where can I delete the current known hosts for the sftp-backup account?

 

[GwenDragon]

Can you connect as root from command line (bash) by: sftp host.domain.TLD

 

[Martin_Sauer]

Yes I can.

Keep in mind, it is pubkey exchange. And all that changed is the remote sftp-Storage-server, so a new host-key. Everything else is the same.

 

[Martin_Sauer]

@IgorG maybe you have an idea? Is there a "known_hosts" for the sftp backup storage? If so, how to modify it? OR what can it be?

 

[Peter Debik]

If a key does not match when doing SSH connections, the system prompts you to accept a new key. If you SSH or sftp to the target as @GwenDragon said and the key does not match, you should have seen such a prompt. Have you?

 

[Martin_Sauer]

If a key does not match when doing SSH connections, the system prompts you to accept a new key. If you SSH or sftp to the target as @GwenDragon said and the key does not match, you should have seen such a prompt. Have you?

It is the sftp storage for backup.

The only thing that changed is the host key of the target server, which hosts the sftp storage. But: all that is automatic.

So my assumption is: there is a known_hosts file, which has the old server key.Which account, where is the file? So I can delete the old known_hosts key.

 

[Martin_Sauer]

Additionally clicking "Backup" in Tools&Settings now takes forever to load.

Once it loads, screen fills with yellow warnings

 

[Martin_Sauer]

Error message on once again confirmation of ssh-storage:

Error: Failed to create the directory "/../../../storage" at sftpstorage.foo.bar: unable to make SSH connection: ssh: handshake failed: ssh: unable to authenticate, attempted methods [none publickey], no supported methods remain

And yes:
1. ssh key is entered correctly
2. yes verified complete ssh key on both sides
3. yes it worked before, exactly this way
4. yes the only thing changed is newly installed sftp-server. Yet userID, groupID, directories are all the same.

MY conclusion: there is a "known_hosts" entry in a file or database for the sftp account, which still lists the old server fingerprint. How/where do I delete that?

 

[Peter Debik]

The SSH known_hosts is located in /root/.ssh/known_hosts. I am not aware of a specific sftp known_hosts file.

 

[Martin_Sauer]

The SSH known_hosts is located in /root/.ssh/known_hosts. I am not aware of a specific sftp known_hosts file.

Please check again. It must be a different account, since root is able to ssh without issues. Maybe chrooted?

 

[Martin_Sauer]

@IgorG Please help?

 

[MarkM]

Igor isn't with Plesk anymore, so it may make more sense to contact the Plesk support team if this is still an issue;

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