EC2にrootでsshする

EC2にrootでsshする:

目的

Ansibleのデバッグや検証でrootでsshしたかった。(ansible_ssh_user=root)

セキュリティホールになるので普通はadminやec2-userでsshしてsudo su -するべし。

やり方

ec2にrootでsshしようとすると怒られてしまうので

ssh -i "key.pem" root@ec2-55-190-222-191.ap-northeast-1.compute.amazonaws.com 
Please login as the user "admin" rather than the user "root". 
 
Connection to ec2-55-190-222-191.ap-northeast-1.compute.amazonaws.com closed. 

rootにスイッチして/root/.ssh/authorized_keysを編集

admin@ip-172-13-10-8:~$ sudo su - 
root@ip-172-13-10-8:~# cat /root/.ssh/authorized_keys 
no-port-forwarding,no-agent-forwarding,no-X11-forwarding,command="echo 'Please login as the user \"admin\" rather than the user \"root\".';echo;sleep 10"  
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCZyYt7/aV7s+X7y3qzABJ6fFV3FitBr3NlDijEEuQT/aBA83L1fOKqjPxD41J0DVYt6yLO9Dmnce8ckXDy/2PM6DPwb8z65/8g5ITEwxq3mcTdmNDAul5zdLnfuDHeOeiEYhCaYetpHqf2gGo65ubVjQc8tl5NLkaX6l7NfUND/fuTxpPoYrhFK2SncdIyh4NUyR71yIWE1kxCTNCTBwMbC0Q5rP7n0Jyb/VPQW15LOdvXcWM7j3+k62uxcc8ZAg5FHdsHlY+qpDr3JYSAbJCew5a1YbbgNW4rqvkYUpooHZXRoYTOXN1a8FEv74kViSSI/zOrZoY2Vn6uKwZoel7H key 

ssh-rsa以前のこの部分を削除

no-port-forwarding,no-agent-forwarding,no-X11-forwarding,command="echo 'Please login as the user \"admin\" rather than the user \"root\".';echo;sleep 10"  

こうなればOK

root@ip-172-13-10-8:~# cat /root/.ssh/authorized_keys 
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCZyYt7/aV7s+X7y3qzABJ6fFV3FitBr3NlDijEEuQT/aBA83L1fOKqjPxD41J0DVYt6yLO9Dmnce8ckXDy/2PM6DPwb8z65/8g5ITEwxq3mcTdmNDAul5zdLnfuDHeOeiEYhCaYetpHqf2gGo65ubVjQc8tl5NLkaX6l7NfUND/fuTxpPoYrhFK2SncdIyh4NUyR71yIWE1kxCTNCTBwMbC0Q5rP7n0Jyb/VPQW15LOdvXcWM7j3+k62uxcc8ZAg5FHdsHlY+qpDr3JYSAbJCew5a1YbbgNW4rqvkYUpooHZXRoYTOXN1a8FEv74kViSSI/zOrZoY2Vn6uKwZoel7H key 

以後rootでsshできるようになる

ssh -i "key.pem" root@ec2-55-190-222-191.ap-northeast-1.compute.amazonaws.com 
Linux ip-172-13-10-8 4.9.0-8-amd64 #1 SMP Debian 4.9.130-2 (2018-10-27) x86_64 
 
The programs included with the Debian GNU/Linux system are free software; 
the exact distribution terms for each program are described in the 
individual files in /usr/share/doc/*/copyright. 
 
Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent 
permitted by applicable law. 
Last login: Thu Nov 22 10:16:13 2018 from 103.2.251.130 
root@ip-172-13-10-8:~#