SSH

Disable warnings when SSH is enabled vSphere ESXi 5

The following steps are what I used to disable this warning on top of my VSphere Client to manage my ESXi 5.x servers.

  1. Select the ESXi 5.x host server in your Inventory
  2. Select Configuration
  3. Select Advanced Settings on the left under the Software menu
  4. Once selected find your way to the bottom where UserVars is located.
  5. Change the value of UserVars.SuppressShellWarning from 0 to 1
  6. Click OK

Cluster warning for ESXi Shell and SSH appear on an ESXi 5.x

Another way to resolve this is to use the esxcli command via the local console or over ssh.

Connect to the ESXi host using the root credentials and run the following command:

esxcli system settings advanced set -o /UserVars/SuppressShellWarning -i 1

 

 

 

For the source of this info and additional steps please check out the VMware KB 2003637

SSH into ESXi 5 host using public key authentication

CLI

I do this with my other linux host over here @ jermsmit.com so why not with my ESXi 5 hosts. Using OpenSSH Public Key Authentication on ESXi 5 required a few things.

  1. You need to enable SSH
  2. You need an SSH client (I use putty)
  3. If you already have a authorized_keys file handy use it or make a new one
  4. And Filezilla or WinSCP handy will also help.

Now all you need to do is locate the following directory on your ESXi 5 host: /etc/ssh/keys-root and copy your authorized_keys file to this location. Unlike standard linux system where the file is located /.ssh/ ESXi has a different layout.

I used WinSCP to do my file copies to my system here, use whatever you feel is best for you. And that’s about it, you can now ssh into yourself w/o the need of entering your password.

Next I think I will attempt my hand at some scripting to automate some tasks; when I do, you will all be the first to know.

Feel free to leave jermsmit.com and head over to this link on Public-key cryptography. The more you know the better we all are

Attach and Reattach to screen session

While using ssh to connect to my home systems to mange my servers (such as Minecraft) I use screen to keep my session(s) open so that if I get disconnected or simply forget and close my putty session I can later resume.  I sometimes find myself in the situation where I go home and later want to attache to my session to only find that I am already attached and this is where I again use screen to join the session that is already in progress.

Here are some sample commands I use normally while during my daily activities.

Attach the running session of screen
screen -r

Attach a specific screen session, you need to use screen -ls to list the running screen’s sessions.
screen -r [name]

and if you are attaching again (reattaching to a session in progress)
screen -d -r

“Permissions are too open”

No man is above the law and no man is below it: nor do we ask any man’s permission when we ask him to obey it. – Theodore Roosevelt

You are attempting to automate your ssh session to a remote system using keys and you get the following “Permissions are too open” message.

The problem is, that the private key you are using must remain private. If you permit others to read it, that condition is not satisfied. So when you type something such as ssh -i ~/.ssh/rsa_key admin@jermsmit.com you get the classic Warning: Unprotected Private Key File!

To change this you simply do the following (make it so only you the owner can read and write to the private key:

This worked for me, it should work for you.

– Jermal

Unsupported Console and SSH on ESXi 4

I haven done this in a long time and took a short while to remember.  So I said why not list the steps here

alt-f1 (Note:  you will not see your typing on this screen).
unsupported
root pw (password)
vi /etc/inetd.conf
delete the “#” from ssh for the IPv4 and IPv6 (If your using it)
services.sh restart