ssh into AWS EC2 instance with botocmdshell

Question

I have a cluster on AWS that I want to SSH into with boto.cmdshell . however maybe I'm not understanding the parameters to pass.

The node has the user ubuntu and no passphrase set.

ssh_client = sshclient_from_instance(instanceobj,
                 ssh_key_file =r'C:\Users\Neil\Downloads\sparkcluster.pem',
                 user_name ='ubuntu')`

I get this error when I run the code:

[Errno 2] No such file or directory: 'C:\\\\Users\\\\Neil/.ssh/known_hosts'

This error makes no sense to me :/, I thought I am supposed provide the pem key to the ssh_key_file parameter. Am I missing something? I know sshing with putty works just fine.

Any help would be awesome!

Answer 1

From what I know and as per the github code of boto , there is one more argument called host_key_file whose default value if not specified by the caller is ~/.ssh/known_hosts . In your case, you don't have that file at your home directory C:\\Users\\Neil . Hence, you get this error.

If you are connecting from a Ubuntu or linux based machine
Add the below lines at the end of /etc/ssh/ssh_config file :

Host IP_YOU_WANT_TO_CONNECT
     IdentityFile path/keyname.pem
     StrictHostKeyChecking no

or do this:

sudo touch ~/.ssh/known_hosts

ssh-keyscan -H [hostname],[ip_address] >> ~/.ssh/known_hosts

In the first case, you may have to specify /etc/ssh/ssh_config as host_key_file . In the second case, the default argument value will work.

There is an equivalent option for windows as well. If you search, you can get lot of information. From what I know, you can install openSSH for windows and C:\\Program Files\\OpenSSH\\etc\\ssh_config is the equivalent of what I posted above for windows. Fill in the information like above in that file. You can then specify this as the host_key_file.
I think you may also manually create a .ssh/ssh_config file in your home directory C:\\Users\\Neil and do something similar to ssh-keyscan I have done above for linux. But, I have never tried this.