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DNS resolution is not working from compute node 

Troubleshooting


Problem

After installing PHPC/PCM 4.x the named.conf contains zone information set to authoritative for the external/public domain which is breaking name resolution.

Symptom

nslookup on deployed computenode for hosts outside of cluster results in failure

Resolving The Problem

Step 1:

Verify the domain information is populated in PCM/HPC web gui

For example:




or use the following command to add the domain name for public network:
for example:
# chdef -t network public domain=contso.com
1 object definitions have been created or modified.

Step 2:
Add appropriate nameserver ip entry by the command below:
for example:
#chdef -t network public nameservers=18.143.2.7
1 object definitions have been created or modified.

Step 3:
Restart the loader:
# plcclient.sh -d pcmnetworkprofileloader
Loaders startup successfully.

Step 4
Recreate named.conf by running the following command:

# makedns -n
Handling .....
..
...
Handling localhost in /etc/hosts.
Handling localhost in /etc/hosts.
Getting reverse zones, this may take several minutes for a large cluster.
Completed getting reverse zones.
Updating zones.
Completed updating zones.
Restarting named
Restarting named complete
Updating DNS records, this may take several minutes for a large cluster.
Completed updating DNS records.
DNS setup is completed

Verify :
cat /etc/named.conf
Should only contain forward and reverse zone entries for the cluster with forwarder IP addresses.

For example:


Do a lookup of host external to the cluster from the computenode.

[{"Product":{"code":"SSENRW","label":"Platform HPC for System x"},"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Component":"DNS","Platform":[{"code":"PF016","label":"Linux"}],"Version":"4.1;4.1.1","Edition":"Standard","Line of Business":{"code":"LOB10","label":"Data and AI"}},{"Product":{"code":"SSDV85","label":"Platform Cluster Manager"},"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Component":"DNS","Platform":[{"code":"PF016","label":"Linux"}],"Version":"4.1.1","Edition":"Standard","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
03 September 2018

UID

isg3T1021528