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jag b

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DHCP migration

Hi Guys ,
im going to add a 2nd DC Server 2012r2 - this will have AD/DNS and will move FSMO roles to this server so this will act as a primary DC - then the other will be for replication/failover.  How do I move the DHCP to the new server? or shall I leave it?? ideally I want to move DHCP to new server...
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DrAtomic
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You can safely use the procedure outlined here: https://support.microsoft.com/en-us/kb/962355/en-us?wa=wsignin1.0 (yes it's about moving w2k3 to a w2k8 server but everything in that article applies to w2k12 as well, plus it can be used for any DHCP to DHCP move).
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Lior Karasenti

Moving the DHCP service to another server in the domain is pretty easy and can be done in minutes.

Check this guide here for steps with screen shots:

http://community.spiceworks.com/how_to/23549-exporting-and-importing-dhcp-database-on-windows-server
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DrAtomic
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Guys - at what point do i uninstall the role from the existing server?  i have tested both below (for my own knowledge) - created a .xml file and also .txtfile on my existing server for below commands:

Export-DhcpServer -ComputerName dhcpserver.contoso.com -File C:\exportdir\dhcpexport.xml

netsh dhcp server export c:\dhcp.txt all

Shall i copy these files onto my new server first? then install the role DHCP? Shall i remove the role DHCP from old server?
How many devices do you have on your network acquiring addresses from the DHCP server?
I recently did exactly what you are doing for 50 users.
The current DHCP server assigned addresses from 192.168.1.50 to 192.168.1.250. Addresses below 192.168.1.50 were reserved for devices with fixed addresses.
I changed the existing DHCP server to only assign addresses in the range 192.168.1.50 to 192.168.1.150. There were no addresses reserved above 192.168.1.150.
I set the range on the new DHCP server to 192.168.1.151 to 192.168.1.250.
I activated the new DHCP server and disabled the old one. It doesn't matter if they are both running at the same time as long as they are serving out different addresses. Each device will take its address from whichever DHCP server replies first.
I waited a until most devices had obtained addresses from the new DHCP server. I then rebooted all devices which still had addresses in the old range.
Once all devices had addresses obtained from the new DHCP server I extended the range to 192.168.1.50 to 192.168.1.250.
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ASKER

im going to do this out of production - no users will be at work.  i have around 100 users... question is - can in install the role on new server - import the file i exported then uninstall from old server?
@Jag

I would do it as follows (after hours):

1. Install DHCP role on new server
2. Stop new DHCP service so it's inactive
3. Export old DHCP database
4. Stop old DHCP service
5. Transfer files
6. Start new DHCP service
7. Import files
8. Restart new DHCP service
9. Verify everything works as intended
10. Uninstall DHCP role on old server

Test the entire procedure in your testlab prior to executing it in production.
The DHCP will become active only ofter you authorize it, so don't forget this step..

http://searchwindowsserver.techtarget.com/tip/Moving-DHCP-without-interruption-during-an-Active-Directory-migration
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Guys - followed below:  Seems to worked on my test - anything i missed?
1. Install DHCP role on new server - done ok
2. Stop new DHCP service so it's inactive - done ok
3. Export old DHCP database
old server i ran:  Export-DhcpServer -ComputerName dhcpserver.contoso.com -File C:\exportdir\dhcpexport.xml
4. Stop old DHCP service - done ok
5. Transfer files - done ok
6. Start new DHCP service
7. Import files
i ran: Import-DhcpServer -ComputerName dhcpserver.contoso.com -File C:\exportdir\dhcpexport.xml -BackupPath C:\dhcpbackup\
8. Restart new DHCP service
9. Verify everything works as intended
10. Uninstall DHCP role on old server

In number 7 - why is the -BackupPath C:\dhcpbackup needed??
anything else that needs to be done here??
In number 7 - why is the -BackupPath C:\dhcpbackup needed??

For rollback purposes, it dumps the original config from before the import is ran in there.
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ASKER

nothing else needs to be done ? or any checks?
my test clients all have IP addresses... and have appeared in my new DHCP scope
For testing you can:

1. Add a new device to the test domain that was previously unknown. make sure it gets it's IP.
2. Completely release the IP on a test workstation, make sure it gets a new IP.
3. Check the renewal on one of the existing workstations to see if it get's a refresh of the IP.
4. Check workstation eventlogs for any obscurities.
5. Check server eventlogs for any obscurities.
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cheers for you help guys