LAN problems after a lightning storm

[DavePL]

We have a 10BaseT LAN in our building, and everything was working well untill last week when there was a thunderstorm in our area, lightning might have struck near our building. The next day a number of people in a room on one side of the building could not log on. It seemed like there were some damaged NIC cards and a mini 4-port hub (set up as an uplink) that was overheated. Replacing the mini hub with a new one allowed two computers to connect, but strangely, we could only use 3 of the 8 ports. The other 5 were inactive, sometimes an alert light would come on, sometimes not. We brought in a new computer to test one of the data drops and found it could log on. However a computer from that room couldn't log on there, but could log on from a different location in the building that is serviced by a different hub! 2 of the 4 data drops in that room seem marginal- some computers can log in but some can't! The hub that was overheated was tried a few days later and it also seemed to work marginally- some computers could log in from it while others couldn't.
We were wondering what safety precautions we can have for lightning? We have not yet tried to power off and on our main hubs, and we may try this during the evening hours.

 

[jimbopalmer]

There are surge protectors for rj45. I would ALWAYS use one if your cable goes outside or between buildings (there are also Cable TV surge protectors if you use a cable modem)

it is possible for 10/100 cards and ports to fail such that 10 works and 100 does not or vice versa, almost sounds like your issue.

I have also found cards that failed such that you HAD to replug them in each time you rebooted the computer, they did not come up when left plugged in. It can look like they work on new equipment when, in fact, they work when first plugged in


I tried to remain child-like, all I acheived was childish.

 

[DavePL]

We have a mix of older 10 mbps hubs and a 100 mbps switch. Somehow the lightning strike made some of the NICs not compatiple with the hub they normally connected to. All our cat5 lines are in one building. We're planning to upgrade our older hubs with a 40-port switch, and hopefully that may be easier to troubleshoot. Meanwhile, replacing the NIC in some of the computers fixed the problem, presumably by boosting the performance. One of the "zapped" computers will log in if we use a shorter cable to the data drop. Were using 4 hubs/switches stacked together which could be the maximum allowable.