Algorithm negotiation failed for SSH Secure Shell Client

1. Use a different system or the console to drop to a shell. Such as Putty
2. Chmod 777 & Edit the “/etc/ssh/sshd_config” file
3. Add all of the algorithm negotiation to sshd_config
4. Restart sshd sevice
   Add following code to sshd_config


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,umac-64@openssh.com,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,curve25519-sha256@libssh.org



root@ubuntu:/home/app# chmod 777 /etc/ssh/sshd_config
root@ubuntu:/home/app# vi /etc/ssh/sshd_config
root@ubuntu:/home/app# service sshd restart