Like most technical folks, I suppose, I'm my family's primary source of tech support. I'm a developer--not a sysadmin--by trade and tonight I bumped into something I've never seen before. I'm hoping someone here has.
In order to better help my Mom, I have her set up on a home network behind a Linksys router (WRT54G). She's got a Mac, so I have her router set up to forward SSH requests to her laptop's internal IP. I also have her router running DDNS through DynDns. Tonight she called to tell me that she can't access the Internet.
Assuming it was one of the many simple, stupid problems most of us encounter with parents, I logged into the router admin remotely and took a look around. Everything looked normal. Then I SSH'd into her machine to check out her IP, DNS, etc. settings. Everything still looked fine. Then I noticed something weird. When SSH'd into her machine, I can't ping her router.
In other words, I seem to be able to access her computer through her router, but not access her router from her computer. A
traceroute dies immediately as well. Any ideas what I might try next? I've bounced her computer and even unplugged her router (it was plugged back in, of course).
Oddly, this could be a problem at the ISP level. I walked her through bypassing the router all together (plugging her computer directly into her cable modem) and she still can't get out (where "get out" means "access a web page using Safari"). What confuses me is that I'm able to get in. That seems very odd to me.