topic Re: DNS lookup in Network Access Control

DNS lookup

amjed.aouissaoui — Tue, 17 Dec 2019 13:37:29 GMT

Hello Experts

I have this problems in ISE 2.4.0.357

Unable to load Context Visibility page. Ensure that reverse DNS lookup is configured for all Cisco ISE nodes in your distributed deployment in the DNS server(s). Exception: blocked by: [SERVICE_UNAVAILABLE/1/state not recovered / initialized];

Help me please.

Re: DNS lookup

Damien Miller — Tue, 17 Dec 2019 14:28:01 GMT

Has the context visibility ever worked? If not, then there is a high probability that the DNS PTR/reverse lookup records are missing ( IP to name resolution). Even if it worked in the past it's still a good idea to confirm your DNS entries.

From the CLI of your ISE nodes enter the following command and confirm that the fqdn is exactly as configured for your nodes.
nslookup <ip address of ise nodes>

Re: DNS lookup

amjed.aouissaoui — Tue, 17 Dec 2019 15:02:47 GMT

Thank u for your answer

but the DNS resolution is work , see the result in picture.

Re: DNS lookup

Damien Miller — Tue, 17 Dec 2019 15:09:41 GMT

Are those FQDN's you performed the lookup on also what is defined on ISE?

Was context visibility working at any point, or is it a new build?

Re: DNS lookup

amjed.aouissaoui — Wed, 18 Dec 2019 16:01:50 GMT

yes , FQDN's is defenied in ISE

Was context visibility working at any point

Re: DNS lookup

Jason Kunst — Wed, 18 Dec 2019 18:47:34 GMT

@amjed.aouissaoui wrote:

Hello Experts

I have this problems in ISE 2.4.0.357

Unable to load Context Visibility page. Ensure that reverse DNS lookup is configured for all Cisco ISE nodes in your distributed deployment in the DNS server(s). Exception: blocked by: [SERVICE_UNAVAILABLE/1/state not recovered / initialized];

Help me please.

Make sure on latest patch, check forward and reverse DNS, restart the system, if still not working, call TAC