A while ago I ran into an issue where I wasn’t able to SSH into a server due to:
Unable to negotiate with 10.123.123.123 port 22: no matching MAC found. Their offer: hmac-ripemd160,hmac-sha1The solution, in my case, involved updating my local ssh config with the proper Message Authentication Codes (MACs), like this:
echo $(ssh -Q mac) | sed "s/ /,/g;s/^/MACs /" >> ~/.ssh/config
Your case may be slightly different, for instance involving Key Exchange Methods, Host Key Algorithms, or Ciphers. To cover all those scenarios you can update your config file as follows:
echo $(ssh -Q mac) | sed "s/ /,/g;s/^/MACs /" && echo $(ssh -Q key) | sed "s/ /,/g;s/^/HostKeyAlgorithms /" && echo $(ssh -Q kex) | sed "s/ /,/g;s/^/KexAlgorithms /" && echo $(ssh -Q cipher) | sed "s/ /,/g;s/^/cipher /" >> ~/.ssh/config