Received the following error from the Azure AD stating that Password Synchronization was not working on the tenant.
When i manually initiate a delta sync, i see the following logs
"The Specified Domain either does not exist or could not be contacted"
(click to enlarge)
Checked the following
- Restarted ADsync Services
- Resolve the ADDS Domain FQDN and DNS – Working
- Test required ports for AD-sync using portqry – issues with the Primary ADDS server defined on the DNS values
Turns out the Domain controller Defined as the primary DNS value was pointing was going thorough updates, its responding on the DNS but doesn’t return any data (Brown-out state)
when checking DNS since the DNS server is connecting, Windows doesn’t check the secondary and tertiary servers defined under DNS servers.
This might happen if you are using a ADDS server via a S2S tunnel/MPLS when the latency goes high
Check make sure your ADDS-DNS servers defined on AD-SYNC server are alive and responding
in my case i just updated the “Primary” DNS value with the umbrella Appliance IP (this act as a proxy and handle the fail-over)
As a Part of my pre-flight check for Vcenter upgrades i like to mount the ISO and go through the first 3 steps, during this I noticed the installer cannot connect to the source appliance with this error
2019-05-01T20:05:02.052Z - info: Stream :: close
2019-05-01T20:05:02.052Z - info: Password not expired
2019-05-01T20:05:02.054Z - error: sourcePrecheck: error in getting source Info: ServerFaultCode: Failed to authenticate with the guest operating system using the supplied credentials.
2019-05-01T20:05:03.328Z - error: Request timed out after 30000 ms, url: https://vcenter.companyABC.local:443/
2019-05-01T20:05:09.675Z - info: Log file was saved at: C:\Users\MCbits\Desktop\installer-20190501-160025555.log
trying to reset via the admin interface or the DCUI didn’t work, after digging around found a way to reset it by forcing the vcenter to boot in to single user mode
- Take a snapshot or backup of the vCenter Server Appliance before proceeding. Do not skip this step.
- Reboot the vCenter Server Appliance.
- After the OS starts, press e key to enter the GNU GRUB Edit Menu.
- Locate the line that begins with the word Linux.
- Append these entries to the end of the line: rw init=/bin/bash The line should look like the following screenshot:
After adding the statement, press F10 to continue booting
Vcenter appliance will boot into single user mode
Type passwd to reset the root password
if you run into the following error message
"Authentication token lock busy"
you need to re-mount the filesystem in RW, which lets you change between read-only and read-write. this will allow you to make changes
mount -o remount,rw /
Until next time !!!