Veeam Backup for Microsoft 365 • Re: v8 new installation - can not add linux proxy

We have exactly the same issue.
- VBO: 8.1.1.159 on Windows Server 2022
- Proxy: Ubuntu 24.04

When we try to add a linux proxy, we get following errors:
[Warning] Warning: Failed to create Rebex (DSS/RSA) SSH connection. Switching to Renci SSH...
[Warning] Warning: Negotiation failed. The client and the server have no common host key algorithm. Server supports 'rsa-sha2-512' which is not enabled at the client.
[Warning] SshStatus: OperationFailure
[Warning] SshRemote: False
[Warning] Status: OperationFailure
[Warning] ProtocolCode: 0
[Warning] ProtocolMessage: Unspecified
[Warning] Warning: The client and the server have no common host key algorithm.
[Warning] SshStatus: OperationFailure
[Warning] SshRemote: False
[Warning] Status: OperationFailure
[Warning] ProtocolCode: 3
[Warning] ProtocolMessage: KeyExchangeFailed
[Warning] SshServerInfo: Rebex.Net.SshServerInfo

We tried:
- SSH /etc/ssh/sshd_config customization --> after that no ssh connection was possible, so reverse
- DNS check (forward and reverse is possible)
- Same time and date on all servers
- Firewall disabled

Has anyone a solution for that from veeam support?

Statistics: Posted by petesteven — May 15, 2025 1:07 pm

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