Lewis' Blog Tales from the trenches of information technology


Multiple default routes / public gateway IPs under Linux

I recently had the need to configure a server for a client with multiple public IPv4 addresses routing to the internet and the requirement to switch between them at will while browsing (http traffic only).

There are a number of articles available on the net dealing with this type of situation, mainly focused on using iproute2, ToS tagging, and Squid (see references, below). However, I bumped into an issue with openSUSE 12.1 where it would stubbornly refuse to accept certain (otherwise valid) ToS (DSCP) values (see https://bugzilla.novell.com/show_bug.cgi?id=770785 for my bug report). This severely limited the number of possible values I could use, and thus, the number of possible public IP addresses.