Can't ping my home ip from an external location

[turtlebrain]

Perhaps this is just coincidence, but last week we had a freak snow storm knock out our power for a couple of days at my home. Ever since then I have not been able to connect via vpn client to or from my work computers.

One of the symptoms I've noticed is that I cannot ping to my home ip address from either work or from a remote server via ssh. I have internet access out, just not back in. Not only do I do the web development but also tech support where I work, so I need to be able to access all pc's in our 5 stores. I've also tried to connect via vnc and ssh with failure. This all worked just fine up until the snow storm.

I'm on comcast cable and have the same ip as for a very long time. Comcast tells me that they can ping to my modem. But other than that the 2 idiots I spoke with last night couldn't even tell me what time it was, never mind actually solve anything. To me, the ping problem is just a possible indicator of what the problem is.

I have both Linux and XP Pro computers at home and at work. At home, I tried bypassing the Linksys router by connecting directly from the modem to each of the computers with the same result. Can get out but not back in. No pings to here possible. Traceroute also will not complete. The VPN client will not connect in any case.

I'm assuming this to be a comcast issue and hopefully today I'll get to speak to an intelligent person there. (Yes, comcast does actually have a few that know what they are doing.) Did something go bad in my modem? In the mean time, I sure would appreciate any suggestions from folks here though.

Edit> Spoke again with comcast this morning. They again tell me that all appears to be fine from their end. I just happened to ask what ip they were showing for me, and it is not the same as what my router or THIS site indicates.

[wimiadmin]

I think your problem is definitely with the Comcast modem.

I have a Comcast business account and my Comcast modem is also a router. Is your Comcast modem the same or is it more of a passive modem where you don't have to open ports on it to allow inbound traffic?

Do you have a reset button on the router to take it back to factory settings?

If it already went back to factory defaults, and it has a built in firewall, perhaps by default the firewall is turned on. But, if you've never had to turn the firewall off in the past, this probably isn't the problem.

If none of the above solutions are the fix, it seems as though there is a DNS problem on Comcasts end pointing any requests for your IP to you.

On another note, my Comcast modem/router shows 2 IPs. This is so they can control it from their end. When they manage the router, they come in on one IP...and if they can get to your modem on that IP, then everything would appear normal to them.

Not sure what it would take to get them to reset their IP routing tables. It'll automatically update at some point.....just not sure when.

You're at the mercy of Comcast. That sucks.

Brian

[AboveTheLogic]

Just a shot in the dark here...

does the modem or router have an option to enable/disable ping replies?

...like I said, a shot in the dark...

also, can you connect to the VPN from a local machine using the server's local IP?

[turtlebrain]

I purchased my own modem some years ago, a Toshiba PCX2200. The router is a Linksys BEFSR41. Since I've tried bypassing the router altogether, that rules that out. There are no modem settings that I'm aware of and no resets other than rebooting it.

On another note, my Comcast modem/router shows 2 IPs. This is so they can control it from their end. When they manage the router, they come in on one IP...and if they can get to your modem on that IP, then everything would appear normal to them.

This is one of the points I tried to get across to comcast. For this reason, I tried to get them to ping and traceroute from command line using the ip available to me, so that they could see what I'm seeing. I was told that even though they are on xp, they are very limited as to what is available to them. So far I've been stuck with 1st tier support and requests for upper levels have resulted in only lip service. It appears that I'll have to contact them via our business account at work to get someone of reasonable intelligence.

For what it's worth, here is a typical traceroute:
1 65.254.51.9 (65.254.51.9) 16.743 ms 0.654 ms 0.736 ms
2 atl-core-g-g3-5.gnax.net (63.247.85.2) 0.495 ms 0.576 ms 0.705 ms
3 ge-6-2.car1.Atlanta4.Level3.net (4.53.232.13) 0.692 ms 0.883 ms 0.705 ms
4 ae-15-51.car1.Atlanta2.Level3.net (4.68.103.10) 0.687 ms 0.883 ms 0.706 ms
5 COMCAST-IP.car1.Atlanta2.Level3.net (4.71.252.18) 17.695 ms 17.583 ms 17.099 ms
6 pos-0-9-0-0-cr01.mclean.va.ibone.comcast.net (68.86.85.74) 16.870 ms 17.349 ms 31.158 ms
7 pos-0-1-0-0-cr01.philadelphia.pa.ibone.comcast.net (68.86.85.2) 20.332 ms 20.693 ms 20.375 ms
8 pos-0-2-0-0-crs01.401nbroadst.pa.panjde.comcast.net (68.86.90.14) 20.707 ms 20.685 ms 20.759 ms
9 be-30-crs01.ivyland.pa.panjde.comcast.net (68.86.208.34) 22.337 ms 22.400 ms 21.980 ms
10 po-10-ar01.verona.nj.panjde.comcast.net (68.86.208.13) 24.953 ms 24.908 ms 24.731 ms
11 te-1-1-ur01.portmurray.nj.panjde.comcast.net (68.86.210.2) 25.212 ms 24.940 ms 24.972 ms
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
and so on until it finally craps out @ 30 hops. I'm just a few miles from Port Murray.

[turtlebrain]

To make a long story short, it turned out to be the modem. VPN still not working quite right, but I expect that has more to do with the new Sonicwall router at work.

[AboveTheLogic]

VPN not working quite right, like how?

Maybe you can try it from another connection?

One way to troubleshoot that I like to do is to use a dial-up account from home to try things from the outside.