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First, ensure all your network fabric uses UPSes.<br />
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The <b>CyberPower CP1500AVRLCD</b> is $130 from Amazon. My guess is you've lost more than $130 trying to deglitch your system after your power outage.<br />
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After all your gear is UPS backed, try cycling power off on everything + then bring up one piece of network gear at a time.<br />
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Sometimes, power on sequences of multiple pieces of gear at the same time, cause negotiation packet storms + some pieces of gear end up confused + don't play well with each other.
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First, ensure all your network fabric uses UPSes.

The CyberPower CP1500AVRLCD is $130 from Amazon. My guess is you've lost more than $130 trying to deglitch your system after your power outage.

After all your gear is UPS backed, try cycling power off on everything + then bring up one piece of network gear at a time.

Sometimes, power on sequences of multiple pieces of gear at the same time, cause negotiation packet storms + some pieces of gear end up confused + don't play well with each other.

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I powered down the 2520 and the hp 5412 and still no luck. I changed the fiber cable on the hp2520 this morning still no activity.
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I powered down the 2520 and the hp 5412 and still no luck. I changed the fiber cable on the hp2520 this morning still no activity.

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I have a HP 2520G switch that connects to a HP E5412zl by fiber connection. We had a power failure in the area of the HP2522 switch. The fiber connect did not come back after power was restored. I replaced the SFP on the HP2522 but still no activity. Any other areas I can check?
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I have a HP 2520G switch that connects to a HP E5412zl by fiber connection. We had a power failure in the area of the HP2522 switch. The fiber connect did not come back after power was restored. I replaced the SFP on the HP2522 but still no activity. Any other areas I can check?

Fiber connection issue

A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.