Hi Thomas! Am 28.12.2021 um 16:24 schrieb Thomas Bohl <openbsd-misc-518...@aloof.de>: > > Hello, > >> My Internet connection is using dynamic IPv6 prefixes. I want to configure a >> local (OpenBSD) machine so its public IPv6 address adjusts to changes in the >> network prefix but keeps a static Interface Identifier (IID). I’d also like >> to be able to configure the IID manually. >> Essentially this would be a server running on the LAN but with a public IPv6 >> address, reachable from the Internet. > > I wrote a script that runs every minute via cron and detects a public IPv6 > network change. On a detected change you could run for example > > ifconfig $interface inet6 alias $newIPv6Net:1:2:3:4 > update-dyndns-whatever > > (You configure what $interface is, and $newIPv6Net is the new network > prefix.) So you always (minus up to a minute) have a working :1:2:3:4 > interface identifier. > > I use the script since four years, but only now decided to publish it. I hope > it is self-explanatory and that my English comments make sense. > > https://aloof.de/f/IPv6Aliases-en.sh > https://aloof.de/f/IPv6Aliases-de.sh
Thanks! You have obviously put a lot of thought into this script and solved a number of potential issues. A couple of observations: - »grep -v '^fd00‘« to remove ULA addresses is not correct. For example the ULA I am using at home starts with fd28:… - Also you are taking separate steps to filter link-local and ULA addresses. Solution to both issues: replace »grep -v '^fd00' | grep -v '^fe80‘« with »grep -vE '^(fe80|fd)‘« At first I thought that using route(8) is overly complicated. But it nicely solves the problem of extracting the prefix which would be much more difficult using ifconfig(8). Mike
