I just bumped into this today when adding a slave node. Seriously, it's been over a year and Jenkins doesn't even support ECDSA.

since connectbot seems to support this nowadays (same client lib?)
https://github.com/connectbot/connectbot/issues/69 ; https://github.com/connectbot/sshlib/pull/26/files
shouldn't this just be an upgrade of the libraries?

This would be great to have updated!!

Can you see to it?

The same goes for other key algorithms.

Or rather, not supporting them is one thing, but showing two pages of stack trace when a user enters one is another thing altogether.

Basic input validation would allow a user to see they entered an unsupported key type without being presented with a stack trace.

This still appears to be an issue with Jenkins 2.73.3 using ssh plugin version 2.5.  ed25519 keys do not work and there is an error stating " Can't connect to server" when attempting to add a new ssh site in the Jenkins global configuration.  See the attached screenshot for refrence.

Jenkins logs also show an error as follows.

ERROR: Failed to authenticate with public key
^{[[8mha:////4IzJAEUbJVXO0x7sOCoWD5u1OPX6pWxoNK4vpa0nY2K0AAAAVx+LCAAAAAAAAP9b85aBtbiIQSmjNKU4P08vOT+vOD8nVc8DzHWtSE4tKMnMz/PLL0mV3NWzufebKBsTA0NFEYMUmgZnCA1SyAABjCCFBQC2xNaiYAAAAA==}[[0mcom.jcraft.jsch.JSchException: invalid privatekey: [B@3802c10b

The key is valid and works when using the ssh client on our jenkins server.

It's still the same in 2.150.1. However, I realize it's a feature (or lack thereof) of the underlying JSCH lib, which doesn't support it either. It only supports ecdsa.