The main router at the office died a few days ago, and I got to spend the morning fixing the problem. It seems like every other week I get a summons to deal with a technical oddity. At least this week’s problem directly affects me, as I hold my internet connection dear to my heart.

Diagnosis

After a little prodding with a multimeter, I determined that the router was probably fine, and that the power supply had failed. After an hour searching through my vast collection of computer parts, I couldn’t find a power supply that would serve as a replacement. Oddly enough, I did find another product by the same manufacturer, that took the same power supply. Unfortunately, its power supply had been lost ten years ago when I moved. I pondered why I was even storing this piece of hardware that had no power supply, then just tossed it back in the bin. It might be useful someday.

I ran a quick patch from the WAN port to my laptop for direct internet access, and started searching for a replacement. The router was well out of warranty, and the manufacturer doesn’t sell individual power supplies. There were a few overseas companies that made compatible power supplies, but they couldn’t ship them very quickly. I ended up finding a guy in Florida who does computer part salvage and sells his parts on eBay, and he had just what I needed. I was able to get a replacement part for a very good price with second day shipping.

Rewiring

Of course, the office can’t run very well without the internet, so in the interim I had to cobble together a fix. Now, I had one other working router on-site, but it was in another room being used as a wireless access point. The power cable was behind a filled bookcase and was very obnoxious to get at.  I wasn’t in the mood to dig it out, only to put it back a few days later. Instead, I used the in-wall cat5 and just patched the WAN line directly into the spare router. I reconfigured the router to act as a gateway, then ran a length of wire across the hall to another room with a free jack, then used this in-wall line to run a LAN port back down to the server room.

There are three switches in this room, all connected to the now unpowered main router.  I rewired them to all connect to each other, rather than the router, then patched the LAN connection from the spare router into one of the switches. Presto, we have internet.

Or so I thought; One computer seemed fine, but most were inexplicably unable to retrieve an IP, or they’d retrieve an IP but in the wrong subnet. After half an hour of trying to deal with this, I patched my laptop directly into the internet again to dig for a little help. This proved to not be very helpful, and I went back to the server room and started looking at the wiring again, to make sure I hadn’t messed something up.

As it turns out, I had. Switch A was connected to Switch B and Switch C, as I had intended, but I had failed to notice one little patch cable connecting switch B to switch C. This created a circular loop, and needless to say was the causing all sorts of odd things to happen. Unhooking this cable eliminated the network wonkiness, and all computers were getting on the internet just fine.

Of course, an hour later somebody tried to print to one of the networked printers, and it failed. I started digging into the printer’s config menu, and it turns out I had originally set it up with a static IP address, rather than with DHCP. I’m not sure why at this point, as its been several years. The problem here was that the spare router was using an entirely different IP than the main router, and the printer was configured to connect through the main router’s IP only. I was unwilling to change the IP address of the spare router at this point, so I toggled the printer to DHCP and tried to print something.

Of course, nothing happened, and more digging produced yet another configuration oddity. When I had installed this printer on all the computers, I had configured the computers to print directly to the static IP address I had assigned the printer. Again, I’m not quite sure why I did it this way. I think it had something to do with trying to avoid an Epson driver issue. In any case, I switched all the computers over to printing to the printer using its NetBIOS name, and all was well. Finally.

Problem Solved

So all told, the power supply of the router dying caused me to spend my morning finding a replacement part, rewiring the network temporarily, reconfiguring the printer, and reconfiguring the printer drivers on all the computers. The upshot here is that fixing those configuration problems will make life easier in the future.

Two days later the part arrived, and I rewired everything back to normal. Thankfully there were no further issues, and everything is running smoothly; At least, until the next piece of technology goes haywire.