68U: Using Dual LAN to work around fried WAN port

[crawfish]

Hi, my RT-AC68U's WAN port was fried by a lightning storm yesterday. Fortunately, none of the devices connected to the LAN ports were affected, and the router seems otherwise fine. With most of my devices on an external switch, I do have one LAN port free, and I've determined I can use it as the primary in Dual LAN for the Internet connection instead of the WAN port. It seems to work fine; speeds are good, firewall activity is logged, etc. My one concern is that the WAN port might be better electrically isolated from the LAN ports than the LAN ports are to one another. That is, I'm worried that if the same surge event that killed the WAN port but spared everything else were to occur now, the LAN ports would be in more danger due to the modem being wired to a LAN port instead of the WAN port. Any ideas on this? Are there any other potential disadvantages?

 

[royarcher]

Hi, my RT-AC68U's WAN port was fried by a lightning storm yesterday. Fortunately, none of the devices connected to the LAN ports were affected, and the router seems otherwise fine. With most of my devices on an external switch, I do have one LAN port free, and I've determined I can use it as the primary in Dual LAN for the Internet connection instead of the WAN port. It seems to work fine; speeds are good, firewall activity is logged, etc. My one concern is that the WAN port might be better electrically isolated from the LAN ports than the LAN ports are to one another. That is, I'm worried that if the same surge event that killed the WAN port but spared everything else were to occur now, the LAN ports would be in more danger due to the modem being wired to a LAN port instead of the WAN port. Any ideas on this? Are there any other potential disadvantages?

Get a surg protector Belkin make very good ones just because it isn't an electrical cable doesn't mean it's not vulnerable they also have a damage reimbursement program if anything gets fried

 

[crawfish]

Everything is on a UPS, but I have no coax or Ethernet surge protection, and I never have had any. I've been doing cable modems since 2000 and never had a problem, nor have I had problems with cable boxes going back 10 years before that, nor VCRs, nor DVRs later on, nor TVs for that matter. This was an exceptionally rare event, and while I've already considered adding coax and/or Ethernet surge protection, I'm really hoping someone can answer the question in my OP. It would be interesting to know! As for surge protection, I would be interested in recommendations on that. I've frequently read that coax surge protection can degrade the signal, and I've never looked at Ethernet, so I'm starting from scratch researching these things.

 

[dave14305]

You’ve found a workaround instead of having to rush out and buy a new router. I would count my blessings and start watching for deals on a new router in due time.

Lightning might strike twice!

 

[OzarkEdge]

As for surge protection, I would be interested in recommendations on that. I've frequently read that coax surge protection can degrade the signal, and I've never looked at Ethernet, so I'm starting from scratch researching these things.

When I jumped up to Gigabit Ethernet, I noticed none of the RJ-45 suppression built into power strips and UPSs were rated above 10/100 Mbps, so read the specs.

OE

 

[crawfish]

You’ve found a workaround instead of having to rush out and buy a new router. I would count my blessings and start watching for deals on a new router in due time.

Lightning might strike twice!

Any reason not to keep using the old router in Dual WAN mode?

The modem was fried, too. I had to replace it. It seemed weird that it booted up normally, and the cable company was able to see it fine. However, the router reported it as disconnected, and it wouldn't work even when directly connected to the PC. (Modem and PC were rebooted, so it definitely should have worked.) I even had them reprovision the old modem today, and there was no change from yesterday.

To summarize, this impressive, unusual lightning storm partially but very sufficiently killed my modem and thoroughly killed the WAN port on my 68U, but it stopped there, thank goodness. This is all a first for me in 30 years. The cable is grounded fine, so that wasn't the problem. The only thing connected to coax was the modem, and nothing else in the house was damaged, so this had to have been a coax surge. While my PC UPS alerted me to an outage, it wasn't long enough to even make the clocks blink on the stove and microwave, which they are wont to do if you look at them wrong.

 

[dave14305]

Any reason not to keep using the old router in Dual WAN mode?

At this point you know what doesn’t work on the router because it was in-your-face obvious. Who knows what else might be lurking on a flash chip or whatever (I’m no EE). I’d be planning on a replacement on my own terms for when that day comes and something else goes on the router. Setup a price watch on slickdeals or camelcamelcamel.com for potential replacements, since you have time to wait.

It’s difficult for me to find a AC68U or 86U locally, so I always need to plan ahead and order online. If my router was damaged once, I’d be devising a plan so the family doesn’t have to “suffer” without the internet waiting for the Amazon Prime truck to come around.

 

[crawfish]

Received replacement 68U today from Amazon. I had actually ordered it Friday before discovering the Dual WAN workaround, and I decided to keep it. Might use the old one for AI Mesh or keep it as a spare. The good news is, I got a B2 revision made in 2019, while my original one was a C1 from 2017. The B2 has a 1.4 GHz CPU vs the C1's 1 GHz, and the UI is a lot faster. Seems weird that the lower revision is more powerful, but there it is. And by a lot faster, I mean the B2 is decent to use. The C1 was unpleasantly slow, the only thing I didn't like about it.