TQSIf lightning strikes a cat6 underground with no protection then the conduit out the ground, nvr, switch and A Amp will blow.
That’s not all. If surge makes its way into your home, the cameras, TV, PC, and other electronics will fry.
If you are really scared about lightning in your area use POE lightning arrester or Ethernet Surge Protectors at both ends and at a minimum just 1 inside and if you can try to ground the surge projector located at the camera end to some metal connected to the ground. No matter what the camera will fry if it gets hit by lightning, there’s nothing you can do about that but it should allow some protection to all other equipment downstream.
Lightning through Ethernet Cable
From my experience and investigation into lightning-induced network damage, the problem typically occurs by having multiple grounds.
For instance, when running an Ethernet cable between two buildings (say, a barn and a house many feet away), each building has its own ground rod.
A lightning strike anywhere in the area creates a big voltage gradient over the surface of the ground, and you could have a brief spike of hundreds or thousands of volts between the two buildings.
A simple fix is to install an Ethernet surge suppressor at each location. Double-check that the suppressor protects all eight Ethernet leads, has a ground lead, and that you connect that wire to a good ground as it won’t offer any protection otherwise.
If there are lightning strikes nearby, you will probably have to replace both suppressors as they often short out with big surges, but do manage to protect your equipment.
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As for the PoE camera on the end of a cable run, make sure it is electrically isolated from a conductive material and freestanding, and throw in an Ethernet surge suppressor at the PoE switch end for a good measure, and you’ll be fine.
Do not make the mistake I made of running additional ground rods and grounding equipment! This is what creates the problem! In the next storm that came over, I had many blown devices, an Ethernet switch with burnt traces, and a PC with the southbridge blown off the motherboard. I eliminated the extra ground rods and moved the ground connection for the network/computer circuit in the barn to the neutral bar in the breaker box (which is connected to the ground rod at the house), and haven’t had any issues since.