Hi everybody, More and more deployments are switching on IPv6, some of them are even 'switching over', by giving mobile devices only an IPv6 address and utilizing DNS64/NAT64 to make this work for IPv4 legacy services. We describe this on http://blog.powerdns.com/2013/05/17/ripe-66-powerdns-and-dns64nat64/
However, today we had a Linux user run into problems with their large IPv6 deployment. The root cause turned to be in the Linux kernel. If you are doing larger scale IPv6 on Linux, check: $ sysctl net.ipv6.route.max_size The kernel-level default is 4096. If you have more IPv6 users than this active simultaneously, things will slow down to a crawl. Today we raised the value to 16384, but far higher values are probably safe too and may be required. We're discussing this the the relevant Linux kernel people here http://marc.info/?l=linux-netdev&m=139352943109400&w=2 but for now, things need to be set manually. Good luck with your IPv6 deployments! Bert _______________________________________________ Pdns-users mailing list [email protected] http://mailman.powerdns.com/mailman/listinfo/pdns-users
