net-ssh behaviour changed in 2.10 from treating a specified algorithm as a preference (and falling back to one it knew) to treating it as a whitelist of algorithms. OpenSSH servers need the algorithm `zlib@openssh.com` rather than plain `zlib`, so negotiation failed. Instead, specify `true` to use net-ssh's list of supported compression algorithms.
Added by Dominic Cleal over 8 years ago
fixes #12632 - remove hardcoded SSH compression algorithm
net-ssh behaviour changed in 2.10 from treating a specified algorithm
as a preference (and falling back to one it knew) to treating it as a
whitelist of algorithms. OpenSSH servers need the algorithm
`zlib@openssh.com` rather than plain `zlib`, so negotiation failed.
Instead, specify `true` to use net-ssh's list of supported compression
algorithms.
https://github.com/net-ssh/net-ssh/blob/v3.0.1/lib/net/ssh/transport/algorithms.rb#L211