[conspire] Testing DNS availability

[Rick Moen]

Might as well share this with others.  (My DNS nameserver is, if memory
serves, a DNS secondary for Ruben's domain.)



Quoting Ruben Safir (mrbrklyn at panix.com):

> FIWI, that means the secondary DNS for mrbrklyn.com et al is all
> working?

Here's how you can get the answer to that question with trivial effort, 
without needing to ask me or anyone else:


:r! whois mrbrklyn.com | grep "^Name Server"

Name Server: WWW2.MRBRKLYN.COM
Name Server: NS1.LINUXMAFIA.COM

:r! dig -t soa mrbrklyn.com @ns1.linuxmafia.com +short

www2.mrbrklyn.com. ruben.www2.mrbrklyn.com. 2013062602 43200 3600 2419200 86400

:r! dig -t soa mrbrklyn.com @www2.mrbrklyn.com +short

www2.mrbrklyn.com. ruben.www2.mrbrklyn.com. 2013062602 43200 3600 2419200 86400


So, yes.  And now you know how to test DNS availability yourself.  Yr.
welcome!

(The point of asking _specifically_ for the SOA record is that it 
permits you in a single query per nameserver to determine not only 
whether the nameserver is answering but also whether it has the same 
zonefile revision as the other authoritative nameservers do.)