lbcd 3.2.4

This is only a documentation change. We ran into a situation where we had a system that not only had multiple interfaces but whose multiple interfaces were participating in different load-balance pools. lbcd when listening to all interfaces (the default) responds on whatever interface the kernel decides is best for reaching a given remote host, but since lbnamed uses the source address to map incoming packets to hosts that it had queried, this meant that one of the interfaces always showed down.

I was going to modify lbcd to always respond on the same interface that the query came from, but it turns out that this is insanely difficult to do. Either you have to use deep magic in recvmsg (and somewhat non-portable deep magic as well), or you have to listen on each interface separately (and thus use deep magic to get a list of interfaces).

So I gave up and just documented the situation and the workaround of running multiple copies of lbcd with the -b flag.

You can get the latest version with the documentation update from the lbcd distribution page.

There's lots of wonderful information on the web, but when it comes to a specific question about Unix network programming, there's still no substitute for Stevens.

Posted: 2006-03-17 23:40 — Why no comments?

Last spun 2013-07-01 from thread modified 2013-01-04