https://access.redhat.com/site/documentation/en-US/OpenShift_Enterprise/2/html-single/Deployment_Guide/index.html#Creating_a_Node_DNS_Record
6.2. Creating a Node DNS Record
There's no real point in specifying the keyfile here; if it's in the standard location, oo-register-dns will just use it. So:

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Update the DNS records (in these instructions, the Host 1 BIND server) to resolve the host name for Host 2. Set the  $keyfile  environment variable on Host 1 to contain the file name for a new DNSSEC key for your domain. Replace example.com in the following command with the domain name you have chosen for this installation:
# keyfile=/var/named/example.com.key
Run the following command on Host 1. Replace example.com with the chosen domain name, node with Host 2's short name, and 10.0.0.2 with Host 2's IP address:
# oo-register-dns -h node -d example.com -n 10.0.0.2 -k $keyfile
==> becomes
Update the DNS records (in these instructions, the Host 1 BIND server) to resolve the host name for Host 2. Run the following command on Host 1, replacing example.com with the chosen domain name, node with Host 2's short name, and 10.0.0.2 with Host 2's IP address:
# oo-register-dns -h node -d example.com -n 10.0.0.2
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Also, the script has been improved a bit and the note should be too:
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This step is not performed by the kickstart or bash script, but can be added if you know the IP address of your node host in advance.
==>
This step is not performed by the kickstart or bash script, but the named_entries parameter can be used to define all hosts in advance when installing named.
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