What is the time period for a domain to remain blacklisted in ISE 2.1 ?

[raghchan]

ISE 2.1 was connected to a particular DC but for some maintenance window the DC was not available for about 2 hours therefore the communication was broken and ISE blacklisted that DC.

But this maintenance window was for only 2 hours but the DC was blacklisted for about 6 hours.

So is there any time period for which a DC will remain blacklisted on ISE.

Regards,

Raghav

[hslai · Accepted solution]

Ideally the network should have at least another domain controller as backup. Nonetheless, blacklisting for 6 hours is quite long. If DEBUG done during the period or it fairly recreate-able in a lab setup, please escalate.