Date: Thu, 24 Dec 2009 00:38:07 -0800 From: Xin LI <delphij@gmail.com> To: FreeBSD Stable <freebsd-stable@freebsd.org>, freebsd-net@freebsd.org Subject: Routing question (GRE packet vs normal traceroute)? Message-ID: <a78074950912240038n19cf1780v5c780c636a998225@mail.gmail.com>
next in thread | raw e-mail | index | archive | help
Hi, A friend of mine has encountered some problem in his setup which consists a pair of GRE peer, one running on OpenBSD and another running FreeBSD 7.2-RELEASE; with 7.2-STABLE, there is no improvement over the situation. The problem we have observed seems to be related to GRE packet not being routed as observed, here is some details: - The FreeBSD box has one network interface connected to two (2) upstream network, with different IP and does not belong to the same subnet, say, one is 1.2.3.4/24 and another is 5.6.7.8/24 - The default gateway can be reached through the first IP address bound to the network interface; - An explicit route has been configured to the OpenBSD host, the gateway being used can be reached directly via the secondary (aliased 5.6.7.8/24) IP. - Both the default gateway and the explicit host route can reach the OpenBSD route. The problem they had is, while traceroute to the OpenBSD host can give the desired result, however, packets that is supposed to be transferred through the GRE tunnel, while they will be encapsulated into a GRE packet, the GRE packet itself won't go to the explicit host route, but end up going to the default gateway. The friend has configured his switch to "bounce" the packet back to the server by configuring a host route on L3 switch, and it seems that the FreeBSD box is able to route the GRE packet to its desired gateway this time. Any suggestions? Cheers, -- Xin LI <delphij@delphij.net> http://www.delphij.net
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?a78074950912240038n19cf1780v5c780c636a998225>