Linux – EC2 Ubuntu SSH Stops Working

amazon ec2linuxsshUbuntu

I use about 15 EC2 instances to run some services. They are hosted on EC2 and run Ubuntu. Every once in a while the SSH stops working and the "Reachability Status" in the EC2 console shows that it is no longer reachable. This doesn't happen to all my servers, just periodically. If I stop and start the server on EC2 the problem gets fixed.

What logs can I look at for more information for why my SSH has stopped working? Does anyone have tips on how I can fix this issue?

Best Answer

I had the same issue. I did a reboot and ssh'ed' into my instance and realised my instance was using too much cpu so it freezed. I was in a free account and also i had limited bandwidth and resources so i decided to upgrade my plan .It helps but is not a happy solution :p

Related Solutions

Linux SSH – Permission Denied (publickey) from Ubuntu to Amazon EC2

The first thing to do in this situation is to use the -v option to ssh, so you can see what types of authentication is tried and what the result is. Does that help enlighten the situation?

In your update to your question, you mention "on another local Ubuntu". Have you copied over the ssh private key to the other machine?

SSH – Bad Owner or Permissions on ~/.ssh/config

I needed to have rw for user only permissions on config. This fixed it.

chmod 600 ~/.ssh/config

As others have noted below, it could be the file owner. (upvote them!)

chown $USER ~/.ssh/config

If your whole folder has invalid permissions here's a table of possible permissions:

Path	Permission
.ssh directory (code)	0700 (drwx------)
private keys (ex: `id_rsa`) (code)	0600 (-rw-------)
`config`	0600 (-rw-------)
public keys (*.pub ex: `id_rsa.pub`)	0644 (-rw-r--r--)
`authorized_keys` (code)	0644 (-rw-r--r--)
`known_hosts`	0644 (-rw-r--r--)

Sources:

openssh check-perm.c
openssh readconf.c
openssh ssh_user_config fix_authorized_keys_perms

Best Answer

Related Solutions

Linux SSH – Permission Denied (publickey) from Ubuntu to Amazon EC2

SSH – Bad Owner or Permissions on ~/.ssh/config

Related Topic