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Re: [LUG] IRC



Neil Stone wrote:
Andrew Pearce wrote:

is  81.91.107.107 the correct ip address for the server,
cant connect to it atm. irc.r-t-f-m.org.uk currently resolves to
that ip.

Nope.. you have a lame DNS server matey...

(no-ip stuff later on)...

Lameness is a specific property of a zone on a DNS server - and not a
general term of abuse for them when they give the wrong answer ;)

Ironicaly lame DNS servers usually return the right answer - but say
they aren't sure about it - so nobody trusts them. I know a quiz team
member like this.

My question would be - what is the output of "dig irc.r-t-f-m.org.uk" on
this machine? - as given that we can figure out if it is stale data or a
broken DNS server somewhere. (or an /etc/hosts entry if the dig answer
is correct ;).

If we are getting picky - CNAME chaining is definitely frowned on by the
RFC's but no one seems to care anymore, at least till they hit the
recursion limits in common DNS resolvers implementations and it all goes
splat.

So purists would make the alias "irc" point to "r-t-f-m.no-ip.info." to
avoid this.... but it won't actually enhance much except save us at most
one look-up and one slot on the resolvers cache table. Goodness (or
compliant to RFC's) has it's rewards - athough sometimes very meagre.

irc.r-t-f-m.org.uk.     86005   IN      CNAME   www.r-t-f-m.org.uk.
www.r-t-f-m.org.uk.     86005   IN      CNAME   r-t-f-m.no-ip.info.
r-t-f-m.no-ip.info.     44      IN      A       80.235.133.27

Argh the "uk" now uses Ultradns and those damn authoritive delegations -
this bugs me - if they have doubts on how the protocol should work they
should copy the reference implementation which doesn't make delegations
authoritative - that is what reference implementations are for after all.

(no-ip stuff)

Bizarrely no-ip.info has a delegation oddity - info delegates to nf2 and
nf3, but the zone claims it is on nf1 and nf2. It is on nf3 - seems a
bit odd you'd think they would list all 3 in both delegation and zone -
no doubt they understand DNS and have their reasons?!

Oh and no-ip.com goes from "ns1" (a.gtld-servers.com) to "nf1"
(n{s|f}1.no-ip.com) - I don't think this will break most name servers
since the IP addresses are the same - but it is the kind of confusion
that makes life hard for computers and humans alike.

Still I can't throw any mud, I'm only 2/3rds the way through my cleaning
up my current zones (only the .org and .uk ones to go) - I need to
fix/replace my DNS testing tools due to the spread of ultradns and those
damn authoritative delegations.

(/no-ip stuff)

Try the host r-t-f-m.no-ip.info  as i said.. dynamic IP address

Ah - but 81.91.107.107 was the right answer once I suspect since;

$ dig -x 81.91.107.107 +short
www.r-t-f-m.org.uk.

Presumably Theo's lot don't tidy these up until they reuse the IP
address. The reverse lookup of an IP address being irrelevant unless you
are using it. Theo's whois data looks very comprehensive - domain
administrative stuff is next on my list of stuff I have to tidy up - hohum.

irc.r-t-f-m.org.uk is a CNAME of r-t-fm.no-ip.info which points to my
dynamic IP address.. phew...

It is worse than that - see above. Phew....

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