I have been playing around with ESXi and needed to upload some files via SCP and discovered that SSH is not enabled by default. There are many sources out there for accomplishing this but I found the following information to be the easiest to follow.
1) At the console of the ESXi host, press ALT-F1 to access the console window.
2) Enter unsupported in the console and then press Enter. You will not see the text you type in.
3) If you typed in unsupported correctly, you will see the Tech Support Mode warning and a password prompt. Enter the password for the root login.
4) You should then see the prompt of ~ #. Edit the file inetd.conf (enter the command *vi /etc/inetd.conf*).
5) Find the line that begins with #ssh and remove the #. Then save the file. If you’re new to using vi, then move the cursor down to #ssh line and then press the Insert key. Move the cursor over one space and then hit backspace to delete the #. Then press ESC and type in :wq to save the file and exit vi. If you make a mistake, you can press the ESC key and then type it :q! to quit vi without saving the file.
6) Restart host or try kill -HUP `ps | grep inetd`
The original blog posting can be found here.