Unable to negotiate with

Unable to negotiate with 55.xxx.455.45 port 30367: no matching cipher found. Their offer: aes256-cbc,[email protected],aes192-cbc,aes128-cbc,arcfour128,arcfour,3des-cbc,none [preauth]

Unable to negotiate with xx.173.152.xxx port 49670: no matching key exchange method found. Their offer: diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1 [preauth]

Unable to negotiate with 10.10.x.x port 22: no matching key exchange method found. Their offer: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1

Solution:
ssh -oKexAlgorithms=+diffie-hellman-group14-sha1 username@hotstname

/etc/ssh/ssh_config
KexAlgorithms +diffie-hellman-group14-sha1

See also: ssh -Q kex SERVER

See also

• SSH clients: ssh (OpenSSH), putty, MobaXterm, plink, mosh, paramiko, conch pssh, sshpass and autossh, sftp, Termius
• sshd, sshd logs, sshd -t, sshd -T, sshd_config, sftp
• OpenSSH (changelog): /etc/ssh/sshd_config | /etc/ssh/ssh_config | ~/.ssh/ | openSSL | sshd logs | sftp | scp | authorized_keys | ssh-keygen | ssh-keyscan | ssh-add | ssh-agent | ssh | Ssh -O stop | ssh-copy-id | CheckHostIP | UseKeychain, OpenSSF