Getting hold of serial numbers

[Stephane Bortzmeyer]

On Wed, Dec 15, 2004 at 03:57:04PM -0800,
 Stephen Carville <stephen at totalflood.com> wrote 
 a message of 40 lines which said:

> USe whois to get a list of dns servers

Bad idea, the information in the DNS itself ("dig NS totalflood.com") is
typically more recent and more reliable.

> Then query each for the SOA record

This can be automated with check_soa (in Liu and Albitz' book, see
http://examples.oreilly.com/dns4/ for the source code):

% check_soa  totalflood.com
ns3.inflow.net has serial number 99
dns.totalflood.com has serial number 99
dns2.totalflood.com has serial number 99
ns4.inflow.net has serial number 99