2 PCs can ping each other, PC1 can ping gw, PC2 cant (solvd)

i92guboj · Last edited by i92guboj on Tue Nov 14, 2006 4:12 pm; edited 1 time in total

Weirdest thing ever... This is the picture: 2 Gentoo amd64 boxes, each one a NIC. All works fine locally. Samba does as well, for the winxp partition in that box. PC1 is 86.111.88.12 and PC2 is 86.111.88.13. Gateway is 86.111.88.1.

PC1 and PC2 are connected to a hub, and the hub goes directly to my gateway. All is rj45, no wireless, nothing fancy. PC1 can ping PC2, all is fine so far. PC1 can also ping gateway, ok. PC2 can ping PC1, and that is really great

But PC2 can't ping my gateway address (and as such, the local net works, the internet, doesn't).

Wince there is a ping between pc1 and pc2, these cables should be fine, and nicks should also be fine. "ping 86.111.88.1" does not work in any of windows xp, gentoo or knoppix, in that box. It can, however, as I previously commented, ping PC1 without any problem.

H4rck · n00b Joined: 29 Jul 2004 Posts: 20 Location: Brussels

Is there any MAC filter on the gateway that would be active (PC1 would then be authorized at the physical level, whatever its IP, while PC2 not)?

If not, then .... good luck! :wink:

_________________
There are only 10 types of people in the world:
Those who understand binary,
and those who don't...

i92guboj · Posted: Mon Nov 13, 2006 5:48 pm Post subject:

I tried several nics, so that should not be the problem. Still I will look a bit more into that, since I am really out of ideas. I will report back if I find anything...

Thank you.

i92guboj · Posted: Tue Nov 14, 2006 4:12 pm Post subject:

I think the problem is mac related. The thing that confussed me is that the cable modem that conects with my gateway seem to do some kind of reset when disconnected. That is why all physicall devices seemed to work fine in this machine, cause I turned of the whole thing each time I changed nics. It might be the modem itself who grab the macs and remembers them while the session is up, and from that momment until reset it only forwards traffic to the outer side from that first registered mac. I am not really sure. But it is the only explanation I can think of.

The physical media is all fine. And the final solution -more like a workaround- has been to just add one more nic in one of the boxes, and then use NAT to setup the rest of them (one now for testing, but they will be more) so they can reach outside thru the one directly connected to the gateway.

Of course, this is just a test, and as I need this box for other purposes, I think that I will just setup any old pentium to do the nat, firewalling, dhcp and dns stuff.