My company has just merged with another, resulting in approximately 75,000 employees. The DNS between the two companies varies from Microsoft NT DNS to Unix/Solaris/BIND 8.2.3. We have a project to determine if we should move to one platform consisting of Lucent QIP software.
What is your opinion on the following: Centralized or decentralized DNS? Windows 2000 or Solaris/BIND 8.2.3? Should DNS and Dynamic Host Configuration Protocol (DHCP) be on the same server? Should we use Lucent Technologies Inc.'s DHCP product or Microsoft Corp.'s?
Centralized DNS works well when you manage all the IP addresses in one IT shop. With two merging organizations you might look at a central DNS server that is configured as secondary for your collection of merging domains. This allows the existing primary DNS servers to do their work while your new central DNS server gathers together the organization's entire DNS database together via zone transfers.
The choice between Win 2000 and Solaris/BIND 8.2.3 DNS is a toss-up, except that Win 2000 DNS is built to work with Active Directory out of the box and BIND isn't. With 75,000 employees, I'd put DNS and DHCP on different servers. QIP is a very strong DHCP management tool, although the Microsoft solution would be my choice if you have big Win 2000 migration plans pending.
Blass, a network architect at Change@Work can be reached at email@example.com.