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- Path: sparky!uunet!spool.mu.edu!agate!doc.ic.ac.uk!uknet!edcastle!festival!ercm20
- From: ercm20@festival.ed.ac.uk (Sam Wilson)
- Newsgroups: comp.protocols.tcp-ip.domains
- Subject: Re: CNAME records and MX/NS records
- Message-ID: <30061@castle.ed.ac.uk>
- Date: 12 Jan 93 11:06:45 GMT
- References: <1isteb$nmc@agate.berkeley.edu>
- Sender: nntpusr@castle.ed.ac.uk
- Lines: 54
-
- cliff@garnet.berkeley.edu (Cliff Frost) writes:
- > It appears reasonable (to me) if you think of providing these services on
- > multiple hosts, so that if one host goes down hard the other one is still
- > providing the function. Eg:
- >
- > ; sam and mary are identically configured for processing email:
- >
- > sam.foo.bar. A 1.2.3.4
- > mary.foo.bar. A 1.2.4.4
- > mail.foo.bar. A 1.2.3.4
- > A 1.2.4.4
-
- Surely what you want here is
-
- sam.foo.bar. A 1.2.3.4
- mary.foo.bar. A 1.2.4.4
- mail.foo.bar. MX 10 sam.foo.bar.
- MX 10 mary.foo.bar.
-
- (yes, you're allowed the same MX preference for multiple entries).
-
- > ; fred and betsy are running identical authoritative nameservers:
- >
- > fred.foo.bar. A 1.2.3.5
- > betsy.foo.bar. A 1.2.4.5
- > ns.foo.bar. A 1.2.3.5
- > A 1.2.4.5
-
- And here you want
-
- fred.foo.bar. A 1.2.3.5
- betsy.foo.bar. A 1.2.4.5
- sub.foo.bar. NS fred.foo.bar.
- NS betsy.foo.bar.
-
- > From experience we can say it works well for mail and less wonderfully (but
- > still useful) for nameservice. The reason it is less useful for nameservice
- > is the slew of software out there which is configurable for one and only one
- > nameserver IP address.
-
- Exuse me if I'm being obtuse here but I don't see what this gains you
- for NSs at all. If the s/w can cope with only one NS address then
- having multiple A records for the same name won't help in the least. It
- probably won't help for things which can use multiple addresses, because
- you can just put the multiple addresses in. The only time it would help
- is if you have something that can take a name and then use multiple
- addresses for that name... but to do that it needs to be able to query
- a nameserver to get the information!!!
-
-
- Sam Wilson
- Network Services Division
- Computing Services, The University of Edinburgh
- Edinburgh, Scotland, UK
-