Meir Kraushar via dns-operations <[email protected]> wrote: > > I looking for insights, usage experience regarding DNAME record > implementation. If any compatibility issues, client side problems, > resolvers etc?.. Highly apperciate If anyone could share their > knowledge.
At Cambridge University we're using DNAMEs for classless reverse DNS delegation for shorter prefixes, originally to minimize the number of zones when 128.232.128.0/17 was delegated, and more recently to handle the way we split 10.0.0.0/9 for departments and 10.128.0.0/9 for the University as a whole. https://tools.ietf.org/html/draft-ietf-dnsop-rfc2317bis https://www.dns.cam.ac.uk/domains/reverse/ It works OK except that we had problems with a mail server: some recipient sites had buggy mailers that could not understand DNAMEs in the reverse DNS so rejected mail. The problem was fixed by changing the mail server's /24 to use a forest of CNAMEs instead of a DNAME. I had wondered if DNAME support had improved enough in the last 10 years to make this workaround unnecessary, but sadly it sounds like there are still too many buggy resolvers :-( There was also some annoyance with the glibc resolver: it would chatter into syslog about unexpected records (i.e. DNAMEs) when parsing DNS responses. This was fixed years ago. Tony. -- f.anthony.n.finch <[email protected]> http://dotat.at/ Ardnamurchan Point to Cape Wrath: North or northwest, backing west or northwest, 4 or 5. Moderate occasionally rough in north. Showers. Good. _______________________________________________ dns-operations mailing list [email protected] https://lists.dns-oarc.net/mailman/listinfo/dns-operations
