On Sat, 2006-05-20 at 14:04 -0700, Andrew Morton wrote: > Paul P Komkoff Jr <[EMAIL PROTECTED]> wrote: > > > > Hello! > > > > I have a userspace application, which talks WCCP2 with cisco routers. > > It sends and receives UDP packets on port 2048. After I've updated my > > server to 2.6.16, it stopped working. > > > > Examining logs and packet dumps of previous (2.6.15 kernel) vs. > > current, I found, that cisco will not understand packets generated by > > 2.6.16. The only difference in that packets was IP id field, which was > > increasing (1, 2, ...) with old kernel, and always 0 with 2.6.16. > > > > Looking thru the changelog, I've found a suspect. It was this commit: > > http://kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1a55d57b107c3e06935763905dc0fb235214569d > > > > Reverting this patch fixes my problems - the router understands > > packets again. > > > > I took a look through the code and ip_select_ident codepath but still > > don't understand why it setting id to 0.
IP id is set to 0 on unconnected sockets when the DF bit is set (path mtu discovery is enabled). Try issuing a connect() in your application and see if the ids are increasing again. -vlad - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
