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What would be a reason you'd have to reboot when you have VPS?
On this scenario at most;
-take corrective action
How do I reboot my Debian 6 VPS - is there an SSH command?
You can reboot your VPS trough Virtuozzo Power Panel (VZPP)
Click here for a video tutorial
Virtuozzo Power Panel (VZPP) is provided with all Linux VPS
plans. It allows you to manage your VPS
in terms of resource monitoring, firewall settings, process monitoring, stop/start/rebooting
and even package and file level updates.
The following works over ssh:
shutdown -r now
Keep in mind you need to be logged in as root or sudo it depending on your OS.
I just learned this today. On redhat, try just "reboot". I think i'll use that since shutdown -r now could be dangerous if you forget the -r.
Imagine shutting the server down through ssh.