These two observations can coexist in one SSH log:

Local forwarding listening on 127.0.0.1 port 1080.
Tunnel device open failed.

The first concerns a dynamic SOCKS listener. The second concerns a tunnel network device. They are separate forwarding requests.

OpenSSH uses -D for application-level dynamic forwarding and -w for tunnel devices. A Tunnel setting can also request the latter through configuration. Failure to obtain the privileges or server permission for a TUN device does not, by itself, prove that the earlier SOCKS listener was never created.

Read what succeeded before the error: SSH authentication, listener creation, and any later destination-channel request. A listening SOCKS port still needs a compatible client and a reachable, permitted destination. It is evidence about one stage.

If the intended job is only SOCKS forwarding, inspect why a tunnel device was requested at all. A scoped configuration can disable that unrelated request:

ssh -N -o Tunnel=no -D 127.0.0.1:1080 [email protected]

Retain the normal SSH host-key and account checks. There is no reason to grant network-device privileges merely to silence an error for a feature the SOCKS route does not need.

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