Hi,
This is a bit of an emergency...
I have an azure tenant that is having issues with Azure AD Domain Services.
As it is suggested, the DNS server were configured in the Vnet as custom DNS.
However, recently there was a complaint that Internet was not accessible from the Azure hosted VM.
I removed the custom DNS servers from the Vnet and switched to "Default (Azure Provided)" and Internet was accessible. However, I could not log on to the VM using my user@customdomain.com account; only with the local Admin account.
Looking at the Azure AD Domain Services Health, there are 2 Monitor messages:
Message 1:
Backup: Last backed up on Sat, 08 Sep 2018 18:51:57 GMT
Message 2:
Synchronization with Azure AD: Synchronized on Thu, 13 Sep 2018 05:59:39 GMT.
And 3 Alerts
Alert 1:
Name: The managed domain is experiencing a network error
Severity: Critical
ID: AADDS104
Raised: 9/13/2018, 10:44:19 AM
Last Detected: 9/13/2018, 5:02:03 PM
Issue: Microsoft is unable to reach the
domain controllers for this managed domain. This may happen if a network security group (NSG) configured on your virtual network blocks access to the managed domain. Another possible reason is if there is a user defined route that blocks incoming traffic from
the internet.
Resolution: Refer
to the following article to resolve this issue Troubleshooting
Alerts - Network Error
Alert 2:
Name: The managed domain has not been backed up for a long time
Severity: Warning
ID: AADDS501
Raised: 9/14/2018, 4:51:57 AM
Last Detected: 9/14/2018, 3:36:16 PM
Issue: The managed domain was last backed up on 9/8/2018 6:51:57 PM.
Resolution: Refer to the following article to resolve this issue Active
Directory Domain Services article
Alert 3:
Name: The managed domain is suspended
Severity: Critical
ID: AADDS504
Raised: 9/13/2018, 5:06:11 PM
Last Detected: 9/14/2018, 3:36:16 PM
Issue: The managed domain is suspended due to an invalid configuration. The service has been unable to manage,
patch, or update the domain controllers for your managed domain for a long time.
Resolution: Refer to the following article to resolve this issue Active
Directory Domain Services article
After doing some research, I was able to ascertain that all 3 ports required for AD Synchronisation (443, 3389, 5986) are defined in the incoming rules of the NSG.
From the Monitor message, the synchronisation was done but the backup was not done for less than a week (if you compare the 2 dates between the backup and the sync).
Apparently, according to https://docs.microsoft.com/en-us/azure/active-directory-domain-services/active-directory-ds-suspension, if the issue is not resolved, the managed domain is at risk of being deleted in less than 15 days.
Of course we would like to avoid this but it seems that the only way we can get this resolved is by having the domain controllers backed up. BUT HOW CAN WE DO THIS!!!?? This is an Azure AD DSmanaged domain.
The same above-mentioned article says the following about a managed domain that is in a "suspended" state:
The "Suspended" state
A managed domain is put in the Suspended state for the following reasons:
- One or more critical alerts haven't been resolved in 15 days. Critical alerts can be caused by a misconfiguration that blocks access to resources that are needed by Azure AD DS.
- There's a billing issue with your Azure subscription or your Azure subscription has expired.
Managed domains are suspended when Microsoft is unable to manage, monitor, patch, or back up the domain on an ongoing basis.
What to expect
- Domain controllers for your managed domain are de-provisioned and aren't reachable within the virtual network.
- Secure LDAP access to the managed domain over the internet (if it's enabled) stops working.
- You notice failures in authenticating to the managed domain, logging on to domain-joined virtual machines, or connecting over LDAP/LDAPS.
- Backups for your managed domain are no longer taken.
- Synchronization with Azure AD stops.
After you resolve the alert, your managed domain goes into the "Suspended" state. Then you need to contact support. Support might restore your managed domain, but only if a backup that is less than 30 days old exists.
The managed domain only stays in a suspended state for 15 days. To recover your managed domain, Microsoft recommends that you resolve critical alerts immediately.
We have a 'Basic' support plan and there were absolutely no change made in Azure portal. So in order for us to have this investigated by Azure support, we have to buy a Support Plan? For something that we didn't break?
Thank you all for your help,
Karim.