F.A.Q. - Frequently Asked Questions and Troubleshooting Tips

Why does my SSH connection hang when I connect to a new host?

If you are connecting to a new host with SSH, the remote host's public key must be known. To get this information, you should log into the host manually with SSH from the machine you are running PyMeter from. The public key will then be automatically transferred to the local machine and inserted in $HOME/.ssh/known_hosts. Once this is done, you should be able to use SSH from PyMeter for remote connections to the new host.

When you do the manual SSH login for the first time, you will see something like this:

$ ssh foo

The authenticity of host 'foo' can't be established.
RSA key fingerprint is
b2:fc:62:5e:5f:06:ca:63:0a:8c:52:03:db:ad:be:52.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'foo,192.168.118.41' (RSA)
to the list of known hosts.

Should I use TELNET or SSH for remote connections?

PyMeter supports both, so the choice is yours. TELNET sends everything (including passwords) in clear text, so this makes it a very insecure protocol and definitely not suitable for communication over the public internet. However, if you are in a secure environment (e.g. on a private network behind a firewall), you may choose to use TELNET because authentication is more lightweight than SSH. Some environments also have security policies that do not allow TELNET, so SSH will be the only method you can use.