Alarms: DNS Resolution Failure
- Description
- DNS Resolution Failure on node
- Suggested Actions
- Check if the dns server configured by the command " ip name-server" is reachable
11-29-2018 07:20 AM
ISE 2.4 version:
Identity Services Engine
Getting DNS error even though Name server is configured. Error "DNS resolution failed for the hostname CNNAME against the currently configured name servers."
Solved! Go to Solution.
11-29-2018 08:08 AM
ok the problem is ISE is not able to do nslookup for hostname.
Please note ISE should be able to do forward and reverse dns lookup for itself and for all other node in the deployment.
11-29-2018 07:25 AM
login to cli of node and do nslookup for the hostname of the ISE node for which you have alarm and check if nslookup is working?
11-29-2018 08:06 AM
Here is the nslookup:
msscidcISE01/admin# nslookup msscidcISE01
Trying "msscidcISE01.mss.tiss"
Trying "msscidcISE01"
Host msscidcISE01 not found: 3(NXDOMAIN)
Received 105 bytes from 209.29.2.44#53 in 1 ms
11-29-2018 08:08 AM
ok the problem is ISE is not able to do nslookup for hostname.
Please note ISE should be able to do forward and reverse dns lookup for itself and for all other node in the deployment.
11-29-2018 08:14 AM
I checked the configuration. I am able to ping Name Server from ISE:
ip name-server 209.29.2.44 209.29.2.45
msscidcISE01/admin# ping 209.29.2.44
PING 209.29.2.44 (209.29.2.44) 56(84) bytes of data.
64 bytes from 209.29.2.44: icmp_seq=1 ttl=63 time=0.604 ms
msscidcISE01/admin# ping 209.29.2.45
PING 209.29.2.45 (209.29.2.45) 56(84) bytes of data.
64 bytes from 209.29.2.45: icmp_seq=1 ttl=63 time=1.01 ms
I don't know where is the issue then?
11-29-2018 08:19 AM
as said before issue is while doing nslookup for hostname of ISE, connectivity is fine.
11-29-2018 08:14 AM
11-29-2018 08:19 AM
What is this then? I guess I have the same issue:
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCur14902/?rfs=iqvred
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