No, a "colo" is an abbreviated term for "co-location" which is a
datacenter that many companies and individuals rent space, power, and
sometimes bandwidth from.
I rent 1U's worth of space, 15a worth of power, and 10mb worth of
internet bandwidth from a company in Manhattan to host my server.
Your idea of DNS replication is, for the most part, correct. They don't
spend much time keeping each other updated. There is a "primary" DNS and
(there should be at least) one or more "secondary" DNS servers. All
changes happen on the primary. When the primary is notified to reload
the zone file after the changes have been made, it will automatically
send out an update to the secondary servers.
When the secondary server gets the update, it looks at the "serial
number" of the zone. If the serial number is newer than the one it
currently is using, it will update itself. If it is not, it won't.
DHSinclair wrote:
Got it! Really great answer. Can I believe that a "colo" is just a
duplicate machine
somewhere else physically that has a replicated database of the local
authoritative
DNS? I'll imagine that these two machines spend their time keeping each
other up
to date......and handle DNS calls from the clients of the network to
which they are
attached....
