Ubuntu 16.04 When you install Openssh-server, you may be able to report this error when you connect using an SSH client, as shown in the following scenario:
Server responded "algorithm negotiation failed"
Modify the server-side SSH configuration file, directory:/etc/ssh/sshd_config, enter the following command to edit
sudo vi/etc/ssh/sshd_config
Toggle edit mode (i), set parameters
Passwordauthentication Yes
Add at the end of the configuration file
Ciphers aes128-cbc,aes192-cbc,aes256-cbc,aes128-ctr,aes192-ctr,aes256-ctr,3des-cbc,arcfour128,arcfour256, Arcfour,blowfish-cbc,cast128-cbc
MACs Hmac-md5,hmac-sha1,[email protected],hmac-ripemd160,hmac-sha1-96,hmac-md5-96
Kexalgorithms DIFFIE-HELLMAN-GROUP1-SHA1,DIFFIE-HELLMAN-GROUP14-SHA1,DIFFIE-HELLMAN-GROUP-EXCHANGE-SHA1, diffie-hellman-group-exchange-sha256,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521, Diffie-hellman-group1-sha1,[email protected]
SSH client re-connects successfully after restarting SSHD service
sudo service ssh restart
Server responded "algorithm negotiation failed" SSH Secure link Server error