Remote DNS Servers

Help !

I recently upgraded our 3 site network to 2000 Server. Site 1 is the primary site housing the first DC running DHCP and DNS. Sites 2 and 3 also house a DC performing DHCP and DNS server roles. Sites 2 and 3 also replicate AD from site 1.

My query is in relation to the actual DNS address I give to the DCs in sites 2 and 3. Do I point the server to it's self or do I point it to the primary server in site 1.

Hope this makes sense

StuartB

I'm going to repeat your question using a kind of diagram approach. If I am wrong explaining your problem, I need to be corrected. Otherwise, your answer follows:

[QUESTION]

You have 3 DNS servers; one server at each site.

ns1.company.com (127.0.0.1)
ns2.company.com (127.0.1.1)
ns3.company.com (127.0.2.1)

all 3 servers hosts the "company.com" domain.

You have 3 webservers; one server at each site.

127.0.0.2
127.0.1.2
127.0.2.2

And you're wanting to know which of the above IP's you should have "www.company.com" point to.

[ANSWER]

I can think of 2 strategies.

1) All 3 servers has the following 3 records:

www.company.com. A 127.0.0.1
www.company.com. A 127.0.1.1
www.company.com. A 127.0.2.1

The result is when somebody resolves your domain, they'll get one of those IP's. This distributes load across all 3 servers. If one of the sites go down, you will lose 1 dns server, and 1 website. People will still be able to get to your website, but there may be some technical difficulties (sometimes a page doesn't display, some clients may not be able to reach the site at all sometimes).

2) Each server points to it's own webserver address:

ns1.company.com (127.0.0.1) has this record:

www.company.com. A 127.0.0.2

ns2.company.com (127.0.1.1) has this record:

www.company.com. A 127.0.1.2

ns3.company.com (127.0.2.1) has this record:

www.company.com. A 127.0.2.2

As a general rule, people should not have different information on different servers. But sometimes this can be useful. The result here is entirely different from the first strategy. If one site goes down, you lose 1 dns server. This may cause technical difficulties resolving the domain - BUT - if somebody DOES successfully resolve a domain, they will only get the IP of a webserver in a site that is still online. That's the advantage, the disadvantage is that you may not get as evenly distributed traffic among the 3 servers even when they're all up. The first listed name server will most likely be resolved the most - which means the webserver on site1 will be getting the most traffic. A second disadvantage is if only a webserver is down (but not the entire site) then ~1/3rd of your clients won't be able to access your site.

It's your choice.