Bind

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cd /etc/bind
vi db.nas-admin.org
3 gets you to the most important line in the whole file

the serial #

every time you make an edit in a db file for bind you MUST update that line or the changes will not be picked up

remember the . at the end

the AXFR is the "zone transfer" to our servers that front for us.

Jan 28 08:30:17 fran named[24445]: zone transfer (AXFR) of "nas-admin.org" (IN) to 

[140.211.166.126].54082 serial 2011012701

so...basically remember 3 things

1) always update the serial

2) cnames are "aliases" for other machines

3) always end the names in the right hand side with a . or else you will get something like this IP Addresses do not need a . at the end.

IF you forget you will get something like this: foo.nas-admin.org.nas-admin.org


if you really wanted foo.nas-admin.org there are 2 wasys to do it

1) just simply foo and it will automagically append .nas-admin.org

2) foo.nas-admin.org.


Then:

service bind restart (or reload)

followed by:

tail -f /var/log/daemon.log


<ka6sox> DNS is a big TREE.

<ka6sox> the top levels (called TLD's) or Top Level Domains are housed in those servers (like 8-9 of them)

<ka6sox> they basically point to things like .org and .tw etc

<ka6sox> and .org is someplace else.

<ka6sox> and .org knows how to get to novaports

<ka6sox> and novaports (us) knows how to get to pulsar

<Jack87> got it

<ka6sox> so in this case the question gets asked 4X

<Jack87> hence... pulsar.novaports.org

<ka6sox> correct

<ka6sox> there are like 5 different main kinds of records

<ka6sox> NS or "nameservers"...these are the nameservers that give the answer to others...

<ka6sox> in our case we are using the nameservers @ osuosl.

<ka6sox> see them?

<Jack87> yup

<ka6sox> okay below that are MX

<ka6sox> mx means "mail exchanger"

<ka6sox> we have 1

<ka6sox> fran

<Jack87> whats gabe?

<ka6sox> if we had several they would all be listed

<ka6sox> OLD long dead server...so this is cruft

<ka6sox> now if we had several the numbers like the 10 mean something

<ka6sox> a number of 10 would be prefered over a 20 server

<ka6sox> below that are the A records

<ka6sox> or Address records

<ka6sox> those point to "our" machines

<ka6sox> below that are the CNAMES or "common names"

<ka6sox> those are like www and other things...

<ka6sox> so blog and mentoring point to fiona

<ka6sox> but www points to fran

<ka6sox> there are a couple of special symbols...

<ka6sox> one is @

<ka6sox> that means just the domain name...aka nas-admin.rog

<ka6sox> er org.

<ka6sox> IP addresses do not need a . at the end

<ka6sox> you see ns1 and ns2 there?

<Jack87> yup

<ka6sox> see anything different?

<Jack87> @ is pointing them to nas-admin.org

<Jack87> @ is pointing them to .nas-admin.org

<ka6sox> so when someone asks for who knows about nas-admin.org the 2 servers that do are ns1 and ns2

<ka6sox> but there is something else different about them.

<Jack87> not an A record?

<ka6sox> no . at the end

<ka6sox> therefore what happens....

<Jack87> .nas-admin.org

<ka6sox> yes, correct..it appends .nas-admin.org

<ka6sox> there are a few more types...but only 1 is in common use

<ka6sox> and thats a PTR

<ka6sox> lets close this

<ka6sox> okay this is called an: in-addr.arpa file

<ka6sox> it contains a list of IP addresses and the names associated with that address

<ka6sox> its also known as the "reverse" lookup table.

<ka6sox> the "dotted quads" are written in reverse order here

<ka6sox> so the real ip addresses are: 140.211.169.x

<ka6sox> but the name is the reverse of that

<ka6sox> 130-190.168.211.140-in-addr.arpa

<ka6sox> when someone says "whats this stupid server @ 140.211.169.165" and asks DNS for its "name" this file is consulted

<ka6sox> and its melo.openembedded.rog

<ka6sox> .org

<ka6sox> this is especially important for mail servers.