How to communicate with legacy ssh server

After updating my open ssh client today I found myself unable to connect to our legacy server:

$ ssh legacy.example.com
Unable to negotiate with legacy.example.com port 12345: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1

And learned something new about ssh. This can be solved on the client side by allowing the legacy algorithm for this server:

Host legacy.example.com
   KexAlgorithms +diffie-hellman-group1-sha1

Hopefully the server side get's an update soon...

Show Comments