k0sctl doesn't read/understand ~/.ssh/config with relation to ssh-agent keys

[warthog9]

Situation: I use individual ssh keys, along with openssh's ssh agent, to deal with connecting to the respective hosts. I can get k0sctl to talk to the agent, however since k0sctl doesn't know about the information in the config file it reads in hundreds of ssh keys, tries them, and ultimately fails because it can't get to the right key.

A work arounds would be to only use a single key across the cluster (arguably not ideal but would work) and load a specific ssh-agent for using k0sctl. However being able to specify the agent key to use would be preferable. I thought I had this working before by setting keyPath, however that seems to (currently anyway) just cycle trying to unlock the encrypted keys and failing (not sure why it attempts to do that 60 times, I suspect that would not change and could be short circuited as well).

I'd propose adding something like agent: to keyPath, but really any way to indicate to the connection to not only explicitly use the agent, but which key in the agent to use would be perfect.

[kke]

It needs to try to sign the key using the agent first, if that works, use it, if the key path was the default, add a fall back to try all agent keys.

Also, it needs to try to get a default keypath from ssh_config before selecting ~/.ssh/id_rsa.

[kke]

Hi, could you check with 0.15.0-rc.1 if it now works as expected?

See k0sproject/rig#73 and k0sproject/rig#75 for more details on the changes

Doesn't address the retrying, that will require a bit of error handling redesign (edit, now done in #427)

[kke]

I assume it was fixed.