Server 2008 x64 to Server 2008 R2 migration for DC's.

Discussion in 'Operating Systems' started by smidley, Dec 28, 2010.

  1. smidley

    smidley [H]Lite

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    Hey guys, I have two domain controllers running Server 2008 x64, and I want to move them both to R2. What do I need to do to make this migration happen? Is there any type of in place upgrade solution? Do I need to do anything with the FSMO roles for this? The servers also take care of DNS and DHCP for my users. And one of them is also a print server. Any kind of basic checklist for this sort of thing would be great. Thanks!
     
  2. mmtom

    mmtom Limp Gawd

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    You can do an in-place upgrade, as long as the current DCs are x64 (which you've already stated).

    Here's my list:
    • Very important: Take a system state backup of one of the DCs.
    • Verify replication topology
    • Verify that replication is healthy between both DCs
    • Check event logs for anything weird
    • Run adprep /forestprep and domainprep on the schema master to prep the domain for R2 DCs
    • Move the FSMO roles off of the server that you're going to upgrade first
    • Verify that the roles have actually moved and that the change replicated
    • Check the location of primary/secondary DNS for each DC
    • Upgrade

    If you had three DCs, what you could also do is completely take down one of the DCs until the upgrade was successful on the other two. That leaves you with a completely intact, untouched DC that you could use to perform an authoritative restore on the other two should things get really FUBAR.

    DNS shouldn't be a concern since users willl hopefully hit the other DC. DHCP will be a problem as users won't be able to get an IP while the DHCP box is down. I can't say for sure about printers as I avoid print servers like the plague :)

    I think that's everything. I'll post more if I remember something else.
     
  3. smidley

    smidley [H]Lite

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    Thanks for the list! I'm currently using DFS-R for replication and haven't ever had any issues with it. I would be doing all of this after-hours when nobody is on the network to avoid any DHCP production downtime.
     
  4. mmtom

    mmtom Limp Gawd

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    You're using DFS-R for sysvol replication? What about directory partition replication? You view that through AD Sites and Services. DFS-R is only for replicating sysvol (policies and scripts at \\domainname\sysvol).
     
  5. smidley

    smidley [H]Lite

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    Can't seem to find that in sites and services.... I thought it just used KCC or something?
     
  6. mmtom

    mmtom Limp Gawd

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    KCC is what figures out the topology and how to replicate based on your site links. So, if all of the site links have been manually created and screwed up, KCC will still try to figure it out based on the bad config.

    What you need to verify is that you have a subnet created for both DCs and that if they aren't in the same Site/subnet in AD that they have links configured. If they both reside in the same site, you don't need to worry about sitelinks. If they're in two different sites (ie, two different subnets), they you need to make sure that the connections are in place and functioning. I'm guessing that they reside in the same site in AD, though.

    The best way to check is repadmin. Run repadmin /showreps from the command line on both DCs and verify that the partitions are replicating inbound on each side. Then run repadmin /replsummary to generate a replication summary. It'll show you if there are or have been any errors.
     
  7. smidley

    smidley [H]Lite

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    Thanks for the tips. I did a replsummary and got no errors.
     
  8. mmtom

    mmtom Limp Gawd

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    Cool. Good luck with the upgrade!
     
  9. smidley

    smidley [H]Lite

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    One last question.... I run all of the FSMO roles on the primary DC, so if I upgrade the secondary one first, then I will need to move all of the FSMO roles to the secondary one once it's been upgraded, then I can perform the upgrade on the primary one correct?
     
  10. mmtom

    mmtom Limp Gawd

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    Sorry, missed that last most. Yeah, upgrade the secondary and when it's successful migrate the roles over.