Domain Controller Down (VM)
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@wirestyle22 said in Domain Controller Down (VM):
I don't actually know how to fix this issue and am very stressed. Typing quickly as a result so please try to bear with me. A user called me and said she thought we had an internet outage. I checked my hypervisor and saw that the DC (2003) was greyed out and inaccessible. I'm assuming we must have had a domain syncing problem before this occurred, otherwise the other domain should have picked everything up as it is round robin. I attempted to disconnect my PC from the domain and reconnect. It claims there are no active directory controllers found.
Be systematic, and slow down. Rushing is going to make things worse. Start by looking at the 2008 Domain Controller. Is it up? Does it have DNS? Is DNS correct? Is it handing out DHCP? Are client machines pointing to it?
That the customer thought that the "Internet was down" suggests that DNS has failed because Domain Controllers normally have nothing to do with getting on a network.
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@wirestyle22 said in Domain Controller Down (VM):
@coliver It's not listed. Can't I use one domain as the primary (FSMO)? Why is that not an issue. I'm sure I'm not understanding something about this.
FSMO roles aren't the issue here. You have a failed domain setup going on. You are imagining problems that don't exist and distracting yourself from the actual issue. Ignore the FSMO roles for now, let's deal with the two things you need to focus on...
- Restoring the VM that is down.
- Figuring out why the other domain controller is not working.
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@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
There we go. Now the answer comes out.
The server holding DHCP and DNS roles is down.
This is the problem.
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@coliver said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@coliver said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@coliver Can't I use one domain as the primary (FSMO)? Why is that not an issue. I'm sure I'm not understanding something about this.
One domain as the primary? There is no more primary or secondary domain controller all of them are now master/master.
Only one has FSMO roles though and that is the server that is down
That's fine. That shouldn't matter you can have the domain controller fail without issues for a little while. Generally a good amount of time as the Master/Master synchronization does its job.
In theory, weeks or more, but.... it sounds like his DCs were not set up properly and don't fail over.
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@JaredBusch said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
There we go. Now the answer comes out.
The server holder DHCP and DNS roles is down.
This is the problem.
Exactly as predicted, simple network configuration error. Not even domain related.
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@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
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@scottalanmiller said in Domain Controller Down (VM):
@JaredBusch said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
There we go. Now the answer comes out.
The server holder DHCP and DNS roles is down.
This is the problem.
Exactly as predicted, simple network configuration error. Not even domain related.
Exactly. Seizing FSMO roles would do zero to resolve the issue.
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@scottalanmiller said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
Willing to bet that the second DNS server is not in the DHCP config so the clients only looked to the first.
BUt that is unfixable at the moment.
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@JaredBusch said in Domain Controller Down (VM):
@scottalanmiller said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
Willing to bet that the second DNS server is not in the DHCP config so the clients only looked to the first.
BUt that is unfixable at the moment.
That's my guess as well.
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@JaredBusch said in Domain Controller Down (VM):
@scottalanmiller said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
Willing to bet that the second DNS server is not in the DHCP config so the clients only looked to the first.
Which would also explain why he can't rejoin the network.
Would still be good to know if the second DC is up and running.
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So ignore everything related to omg, it is a DC.
You simply resolve a normal basic VMWare VM issue.
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@BRRABill said in Domain Controller Down (VM):
@JaredBusch said in Domain Controller Down (VM):
@scottalanmiller said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
Willing to bet that the second DNS server is not in the DHCP config so the clients only looked to the first.
Which would also explain why he can't rejoin the network.
Would still be good to know if the second DC is up and running.
Not relevant to resolving the issue at hand.
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@JaredBusch said in Domain Controller Down (VM):
So ignore everything related to omg, it is a DC.
You simply resolve a normal basic VMWare VM issue.
This ^^^
Time to work through good, old fashioned triage.
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No redundant DNS and no DHCP failover.... basic networking issues. Now that you've discovered them you can fix them permanently.
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@JaredBusch said in Domain Controller Down (VM):
@scottalanmiller said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
Willing to bet that the second DNS server is not in the DHCP config so the clients only looked to the first.
BUt that is unfixable at the moment.
How do I make it fixable? This places backups are absolutely horrendous and I'm sure it is not recoverable. I have been fighting with them to change it and then this happens.
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The fastest thing to do is to do is to simply restore from Veeam/Unitrends/Whatever.
Done up and nothing else matters.
You can then prioritize resolving the fagility in the current setup.
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If you have no backups then you need to look at DHCP and getting a second/new server set up. Or seeing if your firewall has the ability to hand out addresses that may be the quickest way to do it.
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@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch said in Domain Controller Down (VM):
@scottalanmiller said in Domain Controller Down (VM):
@wirestyle22 said in Domain Controller Down (VM):
@JaredBusch It has both. I set a static IP on the computer I am on currently and can connect to the internet.
Now that you are online again, is DNS working on the DC that is up? If so, good. If not, why not?
Willing to bet that the second DNS server is not in the DHCP config so the clients only looked to the first.
BUt that is unfixable at the moment.
How do I make it fixable? This places backups are absolutely horrendous and I'm sure it is not recoverable. I have been fighting with them to change it and then this happens.
If you have no backup, then browse the datastore as we told you and find out if all the VM files are still there.
In terms of DR, the only important one is the VMDK(s)
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@coliver said in Domain Controller Down (VM):
If you have no backups then you need to look at DHCP and getting a second/new server set up. Or seeing if your firewall has the ability to hand out addresses that may be the quickest way to do it.
That is a step down the road if the VM is completely unrecoverable.
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@JaredBusch said in Domain Controller Down (VM):
The fastest thing to do is to do is to simply restore from Veeam/Unitrends/Whatever.
Done up and nothing else matters.
You can then prioritize resolving the fagility in the current setup.
So AD on the down DC would not have been syncing with the other DC he has if DNS was set up incorrectly?
