I have a Dell Poweredge server and Netgear 48-port Gigabit switch, all attached to a CyberPower 1500 VA 900W UPS.
We occasionally get power outages here, and when we do, the systems shut down gracefully, but when the power comes back on, the UPS starts screaming and the devices stay off. The only solve I have right now is to disconnect the server, let the switch power up, and then plug back in the server.
Does this mean I have the wrong UPS for this? Can I somehow 'stage' startups of the devices?
The server is running Funtoo linux, if it helps.
You can invest in a better (more powerful) UPS or an intelligent PDU that staggers switching on devices after a power loss to avoid exactly this problem.
In the Dell BIOS delay the startup, you can delay up to 5 minutes.
That will protect too to be sure the UPS is up and running, not empty in a state of starting / closing if the power come and quit.