[SOLVED] Can't Connect with Static IP

[anuraaga]

Hello,

I've been trying to set up a direct network between two computers, one Windows and the other with Gentoo Linux by hooking them together with a crossover cable. Unfortunately, no matter how hard I try the computers cannot ping each other when I set them up with static IP addresses. I tried setting a static IP address by editing /etc/conf.d/net and specifying an IP address of 192.168.0.2 (the windows box is set up with 192.168.0.3) as well as manually running ifconfig eth0 192.168.0.1 to no avail. Even various permutations of adding network routes was not successful. It is definitely not a problem with the cable because I even tried with a hub and standard patch cables without success (in the end this has to be a crossover cable network though because the Gentoo box is mounted on a mobile robot that moves around). In fact, the strangest thing is when I tried with an Ubuntu livecd, it worked without any issues. The output of ifconfig and routes for Gentoo and Ubuntu were identical, so this has left me scratching my head. As I was in a rush, I went ahead and installed Ubuntu onto the machine after backing up the Gentoo disk to an image file, but I'd like to revert back to Gentoo if possible since there isn't much space on the computer's hard drive and Ubuntu has eaten almost all of it up. Anyone ever experience issues with static IPs in Gentoo? The only thing I can think of is either a problem patch in gentoo-sources or a bugfix patch in ubuntu's kernel sources. The box had no problem connecting to a standard network with DHCP though - the problem only surfaces when trying to set up a private network directly with another computer using either a crossover cable or a hub with static IPs.

[NeddySeagoon]

anuraaga,

Welcome to Gentoo.

I've always found that static networking 'just works' on Gentoo. I'm using baselayout2 and my net file contains.

[anuraaga]

Thanks for the tip. While I had a feeling it has to have something to do with the kernel configuration, it took your suggestion of doing a lspci to get the ball rolling. Running the command showed the system to have a Realtek RTL8168 gigabit network card. Looking at my kernel configuration, I noticed I was using the built in RTL8169 driver. A quick look at the Realtek article on Gentoo-Wiki made it seem like this driver should work with the RTL8168, but there was also an alternate driver provided by Realtek, and I decided it would be worth trying this out. And what do you know, static networking started to work. So while the RTL8169 driver that's included with the kernel may seem to work with the RTL8168 under most normal usage scenarios (DHCP, switches, internet), I guess it must have been incompatible with this particular use case of setting up static networking between two computers with a crossover cable. I'm sure an lsmod on the ubuntu install would have shown it using the appropriate RTL8168 driver instead of the kernel-built in one.

This would be an interesting issue to bring to the kernel driver maintainer's attention, unfortunately I have no idea how to do that

[NeddySeagoon]

anuraaga,

Post a bug to http://bugs.gentoo.org and follow it up as comments are added.
Its quite possible you will be asked for more data than you initially provide on the bug.

The maintainers will be interested in your lspic and lspci -n output for your network interface.
Match them by the numbers at the left, e.g.

[jeffk]

Please let us know what the filed bug id is (or I could file one). I have a Realtek RTL8111/8168B onboard, and it worked perfectly well with a single IP DHCP during buildout setup. Now I'm onsite trying to deploy with multiple static IP's, and I have the following unexpected bugs:

1) Only the first IP is reachable from the outside (e.g. SSH), but the local machine can ping itself to those IPs (UPDATE fixed).

2) DNS name resolving does not work at all, even with the /etc/resolv.conf containing the ISPs and/or OpenDNS nameservers(UPDATE fixed):