Vorta gives a "Connection closed by remote host. Is borg working on the server?" due to faulty key in known_hosts file

[lumbric]

Description

When attempting to start a backup or retrieve the backup list via Vorta, the following error appears:

ERROR - Connection closed by remote host. Is borg working on the server?

However, we successfully connected to the server manually using both an SSH client and Borg (to list backups).

The issue seems specific to Vorta caused by a faulty entry in the known_hosts file: removing the known_hosts file fixes the issue (see below) even if ssh and borg on the command line can connect to the server with the known_hosts file.

Is Vorta somehow connecting to the server in a different way than borg? Isn't it simply a front end to borg?

This seems distinct from borgbackup/borg#636 as it fails immediately after initializing the connection and during the backup. However, this might be related to #1997 and #1104. I don't really understand how ssh-askpass is related to this issue.

Solution: remove known_hosts file

We were able to solve the issue, by doing the following:

1. remove ~/.ssh/known_hosts
2. run a "borg list " on the command line and accept the new host key
3. run the backup in vorta

Environment

• OS: Ubuntu 20.04.6 LTS
• Vorta version: 0.9.1
• Installed from: flatpak
• Borg version: 1.24

Logs

2024-12-07 18:08:19,316 - vorta.keyring.abc - DEBUG - No module named 'objc'
2024-12-07 18:08:19,319 - asyncio - DEBUG - Using selector: EpollSelector
2024-12-07 18:08:19,320 - vorta.keyring.abc - DEBUG - Using VortaSecretStorageKeyring
2024-12-07 18:08:19,320 - vorta.borg.borg_job - DEBUG - Using VortaSecretStorageKeyring keyring to store passwords.
2024-12-07 18:08:19,321 - asyncio - DEBUG - Using selector: EpollSelector
2024-12-07 18:08:19,322 - vorta.keyring.secretstorage - DEBUG - Found 1 passwords matching repo URL.
2024-12-07 18:08:19,323 - vorta.keyring.secretstorage - DEBUG - Retrieved password for repo ssh://<MY_USER>@<MY_DOMAIN>:<PORT>/<PATH>
2024-12-07 18:08:19,346 - vorta.borg.jobs_manager - DEBUG - Add job for site 1
2024-12-07 18:08:19,347 - vorta.borg.jobs_manager - DEBUG - Start job on site: 1
2024-12-07 18:08:19,368 - vorta.borg.borg_job - INFO - Running command /app/bin/borg create --list --progress --info --log-json --json --filter=AM -C lz4 ssh://<MY_USER>@<MY_DOMAIN>:<PORT>/<PATH>::xmg-2024-12-07-180819 <PATHS>
2024-12-07 18:08:19,952 - vorta.borg.borg_job - WARNING - Remote: ssh_askpass: exec(/usr/libexec/ssh-askpass): No such file or directory
2024-12-07 18:08:19,957 - vorta.borg.borg_job - ERROR - Connection closed by remote host. Is borg working on the server?
2024-12-07 18:08:20,124 - vorta.borg.jobs_manager - DEBUG - Finish job for site: 1
2024-12-07 18:08:20,124 - vorta.borg.jobs_manager - DEBUG - No more jobs for site: 1
2024-12-07 18:08:20,130 - vorta.scheduler - DEBUG - Scheduler for profile 1 is disabled.
2024-12-07 18:08:51,042 - vorta.borg.borg_job - DEBUG - Cancel job on site default
2024-12-07 18:08:51,042 - vorta.borg.borg_job - DEBUG - Cancel job on site 1
2024-12-07 18:08:51,042 - vorta.borg.jobs_manager - INFO - Finished cancelling all jobs