Multiple Domain Controllers

Home Forums Server Operating Systems Windows Server 2008 / 2008 R2 Multiple Domain Controllers

This topic contains 4 replies, has 5 voices, and was last updated by Avatar rcoxon 7 years, 10 months ago.

Viewing 5 posts - 1 through 5 (of 5 total)
  • Author
    Posts
  • Avatar
    pcsdps
    Member
    #157091

    I have a physical server that is my operational master domain controller. I have a second virtual (VMWare) domain controller on the same network.

    Both have DNS. The physical server has the primary DNS as itself and the secondary pointing the the virtual DC, and the virtual DC is visa-versa.

    Both have DHCP using the 80/20 rule with the 80 on the physical server, and a 1 day lease.

    My thinking is that if one of the DC’s goes down the other will continue to validate active directory, and hand out DNS and DHCP info to the servers and PC’s. I have tested this by powering down each server separately during the day and making sure everything plugs along fine which it does.

    Last night we had a power outage, my battery backup was drained and all my servers shut down. When power was restored only my physical DC came up (the reason is another story) but none of the other servers or PC’s would work. It was like DNS wasn’t working. After investigating is when I realized that my virtual DC had not powered back on, and once it was back on the computers started working fine.

    So why didn’t my physical DC take care of everything? It’s like everything was looking at the virtual DC instead?

    Many thanks!

    tehcamel
    tehcamel
    Moderator
    #358376

    Re: Multiple Domain Controllers

    check what dns server the effected clients had.

    Avatar
    hazey
    Member
    #339170

    Re: Multiple Domain Controllers

    pcsdps;250160 wrote:
    I have a physical server that is my operational master domain controller. I have a second virtual (VMWare) domain controller on the same network.

    Both have DNS. The physical server has the primary DNS as itself and the secondary pointing the the virtual DC, and the virtual DC is visa-versa.

    Both have DHCP using the 80/20 rule with the 80 on the physical server, and a 1 day lease.

    My thinking is that if one of the DC’s goes down the other will continue to validate active directory, and hand out DNS and DHCP info to the servers and PC’s. I have tested this by powering down each server separately during the day and making sure everything plugs along fine which it does.

    Last night we had a power outage, my battery backup was drained and all my servers shut down. When power was restored only my physical DC came up (the reason is another story) but none of the other servers or PC’s would work. It was like DNS wasn’t working. After investigating is when I realized that my virtual DC had not powered back on, and once it was back on the computers started working fine.

    So why didn’t my physical DC take care of everything? It’s like everything was looking at the virtual DC instead?

    Many thanks!

    what exactly went wrong ? “none of the other servers or PC’s would work” is a bit vague, did they get ip addresses? were they able to log onto the domain? resolve dns names ? etc

    Avatar
    rcoxon
    Member
    #375172

    Re: Multiple Domain Controllers

    Yeah, it is huh?

    DNS was definately a problem, maybe the only one now that the smoke has cleared and I’ve had time to think about it. So let’s assume DNS was the only problem, why didn’t my DC that was up work?

    Avatar
    biggles77
    Spectator
    #212472

    Re: Multiple Domain Controllers

    Is your physical DC set as a GC?
    Have you configured the VMWare VMs to automatically start once the Host has powered back up? I am assuming this option is possible (have to do some VMWare training) because I had this configured when I was using MS Virtual Server 2005 and now in Hyper-V virtuals.

    More importantly, did you UPS gracefully shutdown the Servers when they were draining or did they completely discharge and your Servers went down dirty? If it is the latter, configure the UPS software to do a Graceful Shutdown and then return to a powered state when main power is restored. If you keep getting dirty shutdowns then you will eventually be the victim of file corruptions. Check the HDD state with the following tool: FSUTIL
    c:>fsutil dirty query c: (check any other drives/partitions that you have)
    This tool needs to be run with the console running with Administrator permission. Also, just run fsutil at the prompt and see what other neat utilities you have with this tool.

Viewing 5 posts - 1 through 5 (of 5 total)

You must be logged in to reply to this topic.