~CloudopsDigest~

  If you are managing hundreds of EC2 Linux servers where you need to take ssh frequently so this is very difficult to enter machines login ssh password every time. So below solution will help you to resolve this issue. Commands- login to your main server and follow the step below. 1.ssh-keygen 2. ls -a 3. id_rsa.pub (this is key which need to copy to your destination server) 4. ssh-copy-id <destination host- admin@192.168.*.*>

  Problem-   The authenticity of host 'IP X.X.X.X' can't be established. ECDSA key fingerprint is SHA256:U8lQ0PvPeWJgvTWC+MHS2Idjt4ZxcDzoW5/7kwJ60X0. ECDSA key fingerprint is MD5:2f:73:20:11:42:5e:02:8a:65:5a:f3:e1:2c:f8:ad:57. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added 'host IP' (ECDSA) to the list of known hosts. Permission denied (publickey,gssapi-keyex,gssapi-with-mic). Solution- Sometimes it happens we face above issue while making SSH connection between 2 servers or hosts. Step 1- Make sure ssh server is running  Step 2- Make some configuration changes in SSHD_Config file accordingly. Goto- vi /etc/ssh/sshd_config here we need to make 3 changes 1.Uncommet line- PasswordAuthentication yes 2. Commet Line - #PasswordAuthentication no (This will be line number three) 3. Uncommet- PermitRootLogin yes Step 3- Restart service to apply these changes service sshd restart