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Question on Lightning Protection for Networks

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timby

Occasional Visitor
Here's a little background on the situation. I have FIOS with Verizon supplied Router. My network consists of 4 Desktops, a few laptops (connected wireless) a game console, and two 1gig switches.

These devices are protected by UPS and surge protectors. Last night we had a near hit from lightning. No power disruption. However, my network and POTS phone (wired) went down hard. The router had a red light until I rebooted it. After a reboot it came up with no internet connection. None of my PCs could see each other on the network. :(

Can someone explain to me how lightning could have come across the Cat5 and knocked out the entire network especially those PCs that weren't on? Also, is there some way to protect the Cat5 from lightning?:confused:

I'm in the process of seeing what all permanent damage has been done. I believe I lost most, if not all my NIC's on my PCs. I may have lost a LAN printer (NIC card), and it looks like the switches have ports burnt out. :mad:

Any and all suggestions/recommendations on what to do/check welcomed.

Thanks
 
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With a "near miss" stike, anything is possible. Did the surge protectors indicate that they had tripped?

Remember that most computers are really still on unless you physically pull the plug.

Did the FIOS network box get fried?

Check to see if your surge protectors and UPS came with any sort of damage guarantee. Might be more trouble than it's worth to file a claim, but it's worth checking.
 
Power can travel through virtually any electrical circuit, which includes ethernet. If a strike fried your FIOS box, for example, that could travel through the ethernet network. Most higher end consumer power bars and UPS's have ports for Ethernet and RJ11 connections.
 
With a "near miss" stike, anything is possible. Did the surge protectors indicate that they had tripped?

Remember that most computers are really still on unless you physically pull the plug.

Did the FIOS network box get fried?

Check to see if your surge protectors and UPS came with any sort of damage guarantee. Might be more trouble than it's worth to file a claim, but it's worth checking.

Always appreciate your insights ... :)

Well just so happens the UPS/surge protector that the router was connected to was dark and I had to press the power button. However, it came back on. The router rebooted with the power indicator green and 2 of the port lights green. However, the internet lamp was dark.

I did a loop test (ping 127.0.0.1) on the PCs connected to the network and all returned OK. However, one of the PC's NIC card LED is lit all the time.

I can't remember from my N+ class if the LEDs will light if there is no network connection or if they'll light whenever connected to another device such as a switch. It's a shame to get old and forgetful ....:D

My concern is that I may have problems with the ONT and I believe the Router is toast. Of course maybe it's just the Cat5 from the ONT to the router. However, I feel that would have taken out the router.

I would dearly love to have a device that I could pick up the would test the cables and signals on the LAN.:cool:

Just wishful thinking ...
 
NIC's LED lights can vary from NIC to NIC. Most commonly there's 2 main lights, Connection, and activity. Connection will be lit all the time usually (some will flash or go amber for different types of connections, i.e. 10/000 vs. GigE). Activity lights will usually just flash repeatedly. It all depends on your specific NIC.

And they do make cable testers for RJ-45. You can usually pick up cheap ones for abut $75 all they up to fancy ones by companies like Fluke for several hundreds of dollars.
 
Scotty

Thanks for the reply .... :)

I'm not sure but I'll take a look at the UPS I have the router plugged into and see if it has a RJ-45 connection on the suppressor side.

This is the second time in last couple of years that I had to do some network repair because of lightning. A couple of years ago I got a strike on the cable internet that fried a NIC card. I was told that when the cable was installed that it had lightning protection. That proved to be wrong. :rolleyes:

I just got that new HP 1gig switch less than 2 week ago. :mad:
 
NIC's LED lights can vary from NIC to NIC. Most commonly there's 2 main lights, Connection, and activity. Connection will be lit all the time usually (some will flash or go amber for different types of connections, i.e. 10/000 vs. GigE). Activity lights will usually just flash repeatedly. It all depends on your specific NIC.

And they do make cable testers for RJ-45. You can usually pick up cheap ones for abut $75 all they up to fancy ones by companies like Fluke for several hundreds of dollars.

I always learn something from you guys .... :cool:

So if the NIC is connected to a switch I should get a lit LED? So maybe all is not lost. All but one of the PCs has on-board 1 gig NICs. So I would hate to go through the hassle of installing new NIC cards.

My PC shows when I disconnect the cable from the switch because it tells me that the network cable is disconnected.

We may get this situation straighten out sooner than later. After talking with the Verizon folks last night i didn't have much confidence. Did you know that rebooting the router several times will allow it to heal and possible come back from the dead.....;)
 
I feel for you - I had the same thing happen to me, though we were living a Comcastrophic life back then. Our damage was the router (opening it up revealed a blackened board), the one desktop connected directly to router, and the switch connected to the router.

If I were you, I'd begin by seeing if internal routing is working as you have. If that isn't, I'd begin by replacing the router. If part of your network comes back to life, then start by looking at the switches. Last of all, the NICs. My experience with lightening strikes is that given how little surge protection most computers have, if the computers boot after a strike, the NICs are fine - you'd expect significantly more damage to the motherboard if the surge got all the way through, and that usually means the motherboard has gone to the great mobo in the sky.

As for your FIOS box, your best bet is to get a tech out to look at it. I've found that simply explaining the situation to a reasonably competent tech will get you the box swapped out. Schedule your appointment early in the day - I find that first or second appointments usually yield the best results and the least amount of BSing or paying of fees... "Jim, I know this requires you to step in and charge us, but our house got struck by lightening, can we just do a swap please?" works well in the morning, less so in the afternoon after some cranky appointments.
 
I live in a place called "Thunder Bay" so as you might guess, lightning is pretty common here :) It's important to note the obvious...that not all surge protected power bars are created equal. We had a direct strike on one of our installations and pretty much every cheap surge strip was physically burnt, and everything connect to them, cooked. I still use the APC PER7T power bars specifically because in that strike they performed perfectly with zero damage to connected components.

You mentioned your POTS line went down, which would suggest that current may have hit the PC side of things via a modem line? If FIOS is fibre based, as I'm pretty sure it is, then current could not have entered via your fibre link, however it sounds like a spike hit your router via it's power source. Is every AC plug involved properly grounded and was the router on a proper surge arrester? The aforementioned APC power bars have a status light that indicate a properly grounded circuit which is critical for surge "shunting". You may have an ethernet testing setup that you're not aware of right there. Many motherboards have this feature in BIOS, and some switches (the 3COM 2916) can test cabling too. Check also the wireless connected laptops that likely have hardware diagnostics as part of their driver set. If one of them does, plug it in and test away.

Bottom line though is that as Tim mentioned, all bets are off when a strike hits and "goes to ground". In a direct strike on my childhood home, the house was fine (aside from an entirely freaked out family and a few kitchen cupboard doors flying open), but a submersible pump 160 feet down a drilled well was cooked.
 
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I live in a place called "Thunder Bay" so as you might guess, lightning is pretty common here :) It's important to note the obvious...that not all surge protected power bars are created equal. We had a direct strike on one of our installations and pretty much every cheap surge strip was physically burnt, and everything connect to them, cooked. I still use the APC PER7T power bars specifically because in that strike they performed perfectly with zero damage to connected components.

You mentioned your POTS line went down, which would suggest that current may have hit the PC side of things via a modem line? If FIOS is fibre based, as I'm pretty sure it is, then current could not have entered via your fibre link, however it sounds like a spike hit your router via it's power source. Is every AC plug involved properly grounded and was the router on a proper surge arrester? The aforementioned APC power bars have a status light that indicate a properly grounded circuit which is critical for surge "shunting". You may have an ethernet testing setup that you're not aware of right there. Many motherboards have this feature in BIOS, and some switches (the 3COM 2916) can test cabling too. Check also the wireless connected laptops that likely have hardware diagnostics as part of their driver set. If one of them does, plug it in and test away.

Bottom line though is that as Tim mentioned, all bets are off when a strike hits and "goes to ground". In a direct strike on my childhood home, the house was fine (aside from an entirely freaked out family and a few kitchen cupboard doors flying open), but a submersible pump 160 feet down a drilled well was cooked.

Dennis

Well it seems the ONT's power supply and the Router were toast. After the Tech replaced them I started the arduous task of surveying the damage to the network. It seems that I lost a host of NICs as well as several ports on various gig switches (including the new one I just purchased). The game console seems to be OK and the PC located in the room with the router is fine. It doesn't makes sense. That PC is next to the router that was fried. :confused:

My LAN printer's NIC is toast and will not print. The network sees the device but will not print. I'm going to try and hook it up to a PC through the USB connection and see if it still prints. :mad:

I found some 1 gig D-link NICs ( DGE-530T) local to get the network back up. I would rather have had some Intel's but was unable to find any local and didn't want to wait a week while I ordered from Newegg. Any comments from the house concerning these NICs?

So tonight I get to install 3 new NICs and re-configure the router for my network.

I've made sure the incoming Cat5 is going through the surge on the UPS.

I don't have a warm fuzzy that this can't happen again.:(
 
I've made sure the incoming Cat5 is going through the surge on the UPS.
Huh? How did you do this? The surge protector/UPS has a CAT5 surge filter?

And no, for an almost direct hit lightning stike, there are no guarantees. For best protection, you'd need to unplug everything in a storm like that.
 
Huh? How did you do this? The surge protector/UPS has a CAT5 surge filter?

And no, for an almost direct hit lightning stike, there are no guarantees. For best protection, you'd need to unplug everything in a storm like that.

Tim

It seems that all my UPS have that option as part of the surge protection side.:eek: I connected the CAT5 from the wall into the IN and then the OUT side to the Actiontek router. I'm hoping this will eliminate the problem. However, I don't get a warm fuzzy still. :eek:

You have any comments on the D-link NIC cards (DGE-530T) as I know that you guys typically recommend the Intel ones.
 
You have any comments on the D-link NIC cards (DGE-530T) as I know that you guys typically recommend the Intel ones.

I have two around the house, one in an Vista machine and one in my homebuilt FreeNAS. Under FreeNAS, it works beautifully, and I've had it set to using full-size jumbo frames. Under Vista ... well, something is wrong, because it can't hold a connection for more than a few minutes if you try to use jumbo frames. Otherwise, at an MTU of 1500, it pretty much works as advertised.
 
The 530T's are fine. We've got a few in use....max gigabit speeds we've seen on these using XP is about 40MB/s over the PCI bus assuming a single SATA hard drive is used in the workstation. Timby the chances of another strike (now that you've been hit) are very low. If you're really concerned, have a look at installing a whole-house surge arrester which in my opinion should be part of the building code anyway. This prevents a surge from wandering through your building wiring.
 
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Folks

Thanks for the comments. I'm still trying to get my network back. I spent last evening installing NIC cards and trying to set up the Wireless on the router. I fear my network printer is gone as I can't seem to communicate with it even though it has an appearance on the network. I did a ping and get a responce however, I still can't print.:mad:

I experienced something I've never seen before. I installed a new NIC in one of the older PC's. The system had an on-board NIC that was taken out by the lightning strike. The install went well and the card works fine. However, a few minutes after the PC shuts down the LEDs on the case fans, power-on and HD access blink. If I remove the CAT5 from the NIC the blinking stops. This doesn't happen right away. :confused: Any ideas as to why this is happening? I'm stumped. I took the card out of the system and the problem goes away but then I have no network/internet access.

I'm beginning to think I chose the wrong profession. It seems that home computing consumes what little free time I have just in maintenance. We just got the kinks worked out of the network and now all this. :mad:
 
And no, for an almost direct hit lightning stike, there are no guarantees. For best protection, you'd need to unplug everything in a storm like that.

The best thing I ever read about lighting strikes:

"The only truly safe surge protector for a nearby lighting strike is the 12" of air between the wall plate and the floor where the cables are lying.

I.E. unplug it all if you want to be sure.
 
The best thing I ever read about lighting strikes:

"The only truly safe surge protector for a nearby lighting strike is the 12" of air between the wall plate and the floor where the cables are lying.

I.E. unplug it all if you want to be sure.

Well normally I turn everything off. However, this time it was just a rain storm. There was no warning of lightning as it has just started raining. Typically we see warnings of severe storm in the area.

The words in I lost every NIC card on the network except one. The PC right beside the Router was the only one that was spared. We can't figure out how it was missed. :confused:

Luckily the game console has a wireless connection or we would have had to replace the unit.:)

I told my wife I'm getting tire of trying to keep the network up and running as we get all these weird problems that takes weeks to trouble shoot. :mad:
 
<Warning. Long boring post on surge.>
<Also, I'm open to correction.>

Having devices on surge protectors all over a house doesn't help much in a lighting strike. Or even a near miss. Say anything within 1/2 mile or less.

Here's the deal. Think of a boat on the ocean. A small boat can deal with normal waves. During a storm with higher waves the boat has to ride into the waves to keep from turning over but this is normal. But when that 30+ plus rouge wave shows up you better be prepared to ride over it just right or you'll be in big trouble.

Surges travel through any metal conductor. And a surge like a lightning strike is literally like a wave radiating out from the strike point. And it can travel down a fiber line on the moisture inside or on the casing. And if it hits power lines or a power pole or tower then it travels down the wires AND through the ground. And you CAN'T stop it. It's like trying to stop ocean waves. You can easily get a 10K voltage spike from a nearby lightning strike. The trick is to get your house to ride the wave and not have it smash through it or flip over.

So the first step is getting all your electrical services tied to a common ground point. If your power enters the house from one end and the phone and cable from the other without proper grounding you're going to have issues as the "wave" enters your house from each end. And with a lightning strike you could easily get a 1000+ volt differential between each end of the house. Way more if a nearby strike. So this differential between your power and phone or cable can cause all kinds of damage during it's brief sojourn through your house. TV's, computers, cordless phone base stations, fax machines, etc.. all can get exposed to a very brief but large voltage spike.

So how do you deal with this?

First do your best to get all services to enter a building at a common point with all properly grounded to the same ground stake. If you can't get a common point then at least tie all services to a common ground stake. NOT a ground wire run from the break box. A common stake in the ground with proper ground wires running to each service. This along can keep many nearby strikes from doing much if any damage as it's not the voltage coming down the power or phone that creates most havoc, it's the ground wave.

Second, understand how surge strips work.

All under $200 strips (and likely all under $1000) have variations on design but in general they are designed to handle a certain amount of energy. The "joule" rating. This is not a spring that rebounds after each surge. It's a container that gets filled. A 1500 joule surge suppressor getting hit with a 1000 joule strike will now be a 500 joule surge suppressor. And there's no easy way to measure how much "surge" is left. (Those lights are cute but only trust them with bad news. Don't trust them to show you good news.) So what do you do? I personally write the date I put a surge strip into service. I consider anything under 1500 joules to be a power strip. I consider any surge strip that been in service for 2 or 3 years or to have been exposed to a nearby strike to be a power strip with little or no surge protection. And this is my personal way of doing it based on SWAG. I've yet to see a better way other than using a shorter life expectancy.

Note that most (all?) UPS systems that cost under $500 all basically have a surge strip built in with a battery operated power source that turns on when it notices the power getting too far out of normal. There's nothing magical here in terms of surge protection. And the turn on time of this kind of UPS is way way way slower than the surge duration of a lightning strike.

If a business really wants to be protected without spending $10K or more I go with what many call continuous online systems. These are units where the UPS run is always on. The line connection is always charging the battery and the output is always running off the battery. While a lightning strike can pass through these systems they are better than a typical surge protector as there's no continuous path on the AC circuit. These units start at about $500 and go up from there. And if you have poor quality power they can resolve many issues with networking lockups and glitches that seem to be caused by trolls and other invisible creatures. :)

Sorry for the long post but I think I covered it.
 
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