Power controls
Every instance has the same four power actions, and each one behaves like something you already know from a physical computer. This page explains what each does, when to use it, and how the names line up when you script them.
What each action does
| Action | What it does | Think of it as |
|---|---|---|
| Power On | Boots a server that is currently stopped. | Pressing the power button on a switched-off computer. |
| Shutdown | Asks the operating system to shut down cleanly. Services stop, disks flush, then the machine powers off. | Choosing "Shut down" from inside the operating system. |
| Power Off | Cuts the virtual power at once. Fast, but the operating system gets no chance to clean up. | Pulling the power cord out of the wall. |
| Reboot | A hard power off followed by a power on, for a machine that is wedged and will not respond to a graceful shutdown. | Holding the power button until it dies, then switching it back on. |
Prefer graceful Shutdown for routine stops
When you are stopping a server on purpose, use Shutdown so the operating system can flush data and close services in order. Save Power Off and Reboot for a machine that has stopped responding.
Where to click
Open the server and look at the top right of the page for the power button. Clicking it drops down the menu of the four actions.
Reboot is highlighted here because it is the one people reach for most when a server stops responding. A graceful Shutdown can take a few seconds while the operating system closes down, which is normal.
The names in the API
If you script the panel, the actions carry the same meaning under slightly different names. Three of them match exactly. The one to watch is Reboot, which the API calls POWER_CYCLE.
| Panel | API action |
|---|---|
| Power On | POWER_ON |
| Power Off | POWER_OFF |
| Shutdown | SHUTDOWN |
| Reboot | POWER_CYCLE |
For the full request format, batching several servers in one call, and examples you can copy, see the API power reference.
Related
- VNC console get onto the machine's screen when a reboot alone does not fix it.
- Passwords & reset set a known password before you log in at the console.