ISE 1.x : Configured nameserver is down / not reachable

[Frank Lothar Weber]

Hi, folks.

has anybody an idea why ISE 1.x (1.4 exactly) is constantly throwing an alarm that one/all of the configured nameservers may be down ??

This alarm constantly repeats, but the configured nameservers are of course reachable and the dns service is running smoothly.

Rgs

Frank

[Omar Sandoval]

Do you have a solution for this alarm?

Regards.

[Markus Baumgartner]

We have the same Problem with ISE 1.4.

Network connectivity is OK, 

any Ideas??

best regards

Markus

[SHANNON WYATT]

The new patch seems to have fixed this, but now I have a NTP error that is coming up (Doh!)

[ajc]

NTP does not work properly on ACS and ISE when you are using a Windows NTP Server as clock source (I will post later the links with the info). I had to configure an intermediate switch as clock master for ISE's (workaround). This switch was getting the clock from the Windows Server with no issues. I am still working on this.

[Frank Lothar Weber]

Hey, Shannon.

What patch are you referring to exactly .. ??

Rgs

Frank

[SHANNON WYATT]

ise-patchbundle-1.4.0.253-Patch3-141133.x86_64.tar.gz

Dated August 4th.

[ajc]

From my TAC Case:

The problem that you have with the ISE server and the NTP is a know issue that ISE has with the windows servers.

We found documentation that says that ISE server has problems with the NTP server for windows, as recommendation we point the ISE server to a local switch that was configured as ntp server, the Ise sever are now synchronized with the switch.

There are different recommendations to resolve this problem:

1. Use a different server instead of windows ntp to do the time synchronization.

2. Use a Cisco device like a switch or router as an NTP server to synchronize the ISE server.

These are the links about the problems:
http://www.cisco.com/c/en/us/support/docs/ip/network-time-protocol-ntp/116161-trouble-ntp-00.html
https://supportforums.cisco.com/discussion/11619556/synchronizing-cisco-ise-and-ntp-server

[ajc]

Hi Frank,

Could you please click on the blue circle and post here an screenshot with the content. I am running 1.4 patch 3 and I have not seen that warning.