Changing ip address of server and dhcp

[esu4edp]

I'm stepping in for a guy who left, and im a bit new. My company wants me to change our internal ip address from a 192.168.10.X/24 scheme to a 192.168.90.X/24 scheme. My question is this. What all do i need to change. Do I change the scope on the server? Do I change the allowable addresses under DHCP? Do I go under network connections for the server and change the manually set ip address and gateway? Any other place I need to change things. And after that is done, all the other computers that log onto the domain should be able to connect just like before it was changed(with the new ip address)? We have Win Server 2k3 and use active directory!

 

[58sniper]

You have to manually change the IP address on every statically assigned device in your network. This is likely all servers, routers, switches, firewalls, access points, etc.

It may also include printers.

You also must create a new DHCP scope.

Pat Richard
Microsoft Exchange MVP

 

[lhuegele]

Is there a reason behind why your company want's to make this change?

 

[theravager]

have look into netsh, if you dhcp is pretty complex exporting it and editing it in a text editor then reimporting would be possible easier.

 

[58sniper]

And chop your current lease time down to something ridiculously short - like 4 hours. That way, when the time comes, machines will pickup the new addresses quicker. After you're totally moved over, you can crank the lease time back up.

Pat Richard
Microsoft Exchange MVP

 

[esu4edp]

we are joining networks with another company and they are already setup on that network scheme, so in order to keep from having any conflicts with ip addresses they want to change to the 192.168.90.???/24 scheme. So I just wanted to make sure when I did this that I would get everything correct! Im just not that technically confident yet by doing something myself. Im pretty sure I know what to do, I just am new and forget things and dont always think of everything right away until there is some kind of problem!

 

[LawnBoy]

You could just change the mask to /16, problem solved...


"We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth." - Sherlock Holmes

 

[Davetoo]

Except for the potential of all the duplicate static IP addresses because both companies are currently using the 192.168.10.0/24 subnet.

I'm Certifiable, not cert-ified.
It just means my answers are from experience, not a book.

 

[LawnBoy]

we are joining networks with another company and they are already setup on that network scheme

I take this to mean the other company is already using the .90.x addressing. So no conflicts.



"We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth." - Sherlock Holmes

 

[esu4edp]

We are both on the 192.168.10.???/24 scheme, we are going to change to the 192.168.90.???/24 because we have less computers and printers and things so its easier for us to change everything then it is for the other company.

 

[Davetoo]

Thus...conflicts. You can't just use a /16 subnet, it won't work.

I'm Certifiable, not cert-ified.
It just means my answers are from experience, not a book.

 

[LawnBoy]

Yup, I misunderstood.



"We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth." - Sherlock Holmes

 

[Roadki11]

Dont forget about dns. Probably need to dump your forward and reverse lookup zones and make new ones. Need to ensure all clients reregister, should also run some sort of login script that does an ipconfig /flushdns on all clients.



RoadKi11

"This apparent fear reaction is typical, rather than try to solve technical problems technically, policy solutions are often chosen." - Fred Cohen