What is this all about???

[Shon Stephens]

I am using BIND 9.1.1. I have a master and slave server for my domain. When I do nslookup (I know,  everyone wants to use dig). I do:

nslookup
set type=any
domain.com

It returns something like this:
domain.com
        origin = ns1.domain.com
        mail addr = hostmaster.domain.com
        serial = 1
        refresh = 86400 (1D)
        retry   = 3600 (1H)
        expire  = 604800 (1W)
        minimum ttl = 86400 (1D)
domain.com        preference = 10, mail exchanger = mail.domain.com
domain.com        nameserver = ns1.domain.com
domain.com        nameserver = ns2.domain.com
domain.com        nameserver = ns1.domain.com
domain.com        nameserver = ns2.domain.com
mail.domain.com internet address = 10.1.1.172
ns1.domain.com internet address = 10.1.2.190
ns2.domain.cominternet address = 10.1.2.191

My db file only contains 2 entries for the NS records. 1 for each of the name servers. Why do I get 4 entries when I perform this query?

Thanks,
Shon