need to (live)migrate dhcp from win2k srv to new sol10

[williez]

my company is surviving on its single win2k server handling all dhcp,dns,filesrv,email, etc. i'm looking to migrate off before it crashes under me to (a few?) solaris 10.
i cant afford downtime more than a few minutes at a time, and am not a Windows man, except by hunt-n-peck. i have <10 workstations with a mix of win2K and WinXP, half mission-critical.
any suggestions and/or best-practices to safely cut over piece by piece off of windows as much and as quickly as possible?
my idea is to create a Solaris10 server w/out dhcp dependencies, then make Sol10 a dns backup, then make Sol10 the primary. Then restrict some ip's from the Win server, then enable those ip's with DHCP on the Sol10 and cut over each client. somewhere in there offload fileserving to the nearly file-static environment from Win to Sol10.

I've never done these things, but it seems a good order.
suggestions?
Thanks. :^)

 

[SimonDavies]

I have to be honest with you and say that by reducing the lease time of your DHCP server to something like 12 hours and your DHCP environment doesn't have any reserved addresses set up in it (for servers etc) you would probably be fine building up your Solaris Box now, replicating the existing scope and going live with the new server over a weekend, you would need to decommission the existing server at the same time and to test connectivity you would simply do an ipconfig /release and then ipconfig /renew (I always have issues doing a straight /renew).

Failing that have a look have a look at the resource kit for DHCPexim but in all honesty I would go with my first suggestion (unless you have a lot of data and reserved addresses in it).

Simon

The real world is not about exam scores, it's about ability.

 

[MichealC4]

When I do a migration like this, I like to put up the new server(s) in a test environment, scrounge around for a few machines, or a few non-critical production machines, test them, decommission the old machine, rollout, and on Monday if all was tested well, there will be little to no smoke to clear.

In other words, what SimonDavies suggested is mostly the way I would do this, with the exception of putting the new Solaris 10 on a separate vlan if possible to make sure I replicated the DHCP settings correctly.

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