This if from the article on Yellow Bricks: Enable SSH on ESXi 4.1 | Yellow Bricks
There are two different kind of Tech Support Modes:
- Local Tech Support (Commandline access)
- Remote Tech Support (SSH)
Enabling either of the two is really simple:
- Open the ESXi console
- Login(F2) and go to “Troubleshooting Options“
- Now you will see options called “Tech Support”, hit “enter” on either Remote Tech Support (SSH) or Local Tech Support
You could of course also enable it through the vSphere Client:
- Select the host and click the Configuration tab.
- Click Security profile > Properties.
- Click Local Tech Support or Remote Tech Support (SSH) and click Options.
- Choose the desired startup policy and click Start, then click OK.
- Verify that the daemon selected in step 3 shows as running in the Services Properties window.
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