I had to change the DNS-Servers on the two ISE 2.7 of our customer.
I did this on the CLI and got the information that a reload is necesary
that the change have effect.
I reloaded the second ISE node and the node was accessible after approx. 3 minutes again.
Then I reloaded the first ISE node and I could not access the node anymore then. After
a long time I could access it again the monitoring reported an outage of 28 minutes!
The customer wants to know the reason for this long outage.
I found the possibility for a 'Health Checks' under 'Administration' in the GUI (see screen dump).
1. Does it make sense to find out more about the reason for the long outage and can I
let run this during normal office hours or does it pull down the ISE perfomance?
2. Is there any other I can do to find out more about the reason for the long outage?
Thanks a lot for every hint!