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DNS Configuration in Solaris 10

DNS Configuration in Solaris 10
I like to share configuration of DNS primary and secondary in solaris 10. This implementation was done in a solaris 10 X86.Solaris 10 comes with Bind 9.3 version.

Step 1:

Include the name server in a /etc/resolv.conf file



Here domain name is dev.test.com and there are two name servers defined(192.168.0.1 and 192.168.0.2)

step 2:

Change hosts in nsswitch.conf to point to dns.



Here while querying, it will first look in hosts file then it will go for dns server

I am going to include following host name and ip address in DNS. For this we need to create forward and reverse lookup zones.

Sun10 --> 192.168.0.1
sunclient --> 192.168.0.2
sunclient1 --> 192.168.0.3
sunclient2 --> 192.168.0.4
sunclient3 --> 192.168.0.7

Setting up Primary DNS server

In the below setups i am going to create a zone for domain dev.test.com

Step 1:

Configure /etc/named.conf file. If the file is not available areate new named.conf file




In the above file Secret keys are generated using command "rndc-confgen". We need to include this key in primary and secondary servers named.conf file
for secured zone transfer.

Directory is path where zone db files were kept. Here zone db files were kept in /var/named. We are using type as master since this is a primary server
and the db file name is db.dev and this is kept in path /var/named. Here i created both forward and reverse lookup zone


Step 2:

We need to create domain zone file in /var/named. I am going to create three files for the three zones.




Step 3:

Create named.boot file in /var/named



Thats it we are done

Start dns using either /usr/sbin/named or svcadm enable dns/server




Setting up secondary servers

A Secondary DNS Server is basically just a backup server. I does not hold the master versions of the zone information but rather it holds copies of them. Most sites use Secondary servers in remote locations or to cut down on the load on the Primary server. The Secondary server performs zone transfers at said times making sure it has the newest versions of the zone information.

In order to configure secondary server. we need to make few changes in primary servers zone db file.

Include secondary servers name in db file. I have included secondary server name sun10 in db.dev file, db.192.168.0



Here NS sun10 is secondary server. The same should be included in other zone file db.192.168.0.

create /etc/named.conf file in secodary server



Here i have included type as slave as it is secondary server. we are done now

Because this is a Secondary Server, there is no need to do anything with zone files. BONUS! As long as you have everything setup right on your Primary and your named.conf file is configured properly, everything will work properly.

Each time the Primary site's zone files are modified and the Serial # is incremented, BIND will send out a notify to all Secondaries (any server in the zone file with a IN NS statement) stating a change has been made. BIND on each of these servers will then check it's own zone files to see if it has the same version or not. If the version that the Primary has notified it about is newer then it will perform a zone transfer and obtain the newer version.

If everything is setup properly, you will never need to make any changes to your Secondary server except to upgrade BIND itself. All changes from here on out should be made on the Primary server. The exception is if a new zone is added on the primary, you need to add it to the secondaries also if you want them to be secondary to the new zone.

Thanks,
Rajeev