OKD - Create a Homelab Cluster

OKD - Create a Homelab Cluster - DNS

We'll be working on the Servers that are surrounded by the continous lines in this drawing:

I'm using FreeIPA as my authoritative DNS Servers for my homelab. I'll be using a separate dns zone for all servers of this cluster as well as the helper nodes. The helper nodes will be provisioned by my foreman server, so they're already integrated with FreeIPA and no dns records or domain-joins will have to be performed on these servers.

I'll be using an additional DNS Zone for my OKD Cluster: 'okd.archyslife.lan'. Create the zone using the ipa cli utility:

 [archy@ipa03 ~]$ ipa dnszone-add okd.archyslife.lan --dynamic-update 'true' --forward-policy 'first' --allow-query '127.0.0.0/8;172.31.10.0/24' --allow-sync-ptr 'true'

We'll also be needing dns records for each node, 'api', 'api-int' and '*.apps', so let's create them:

 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan bootstrap --a-ip-address '172.31.10.150' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan master01 --a-ip-address '172.31.10.151' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan master02 --a-ip-address '172.31.10.152' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan master03 --a-ip-address '172.31.10.153' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan worker01 --a-ip-address '172.31.10.154' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan worker02 --a-ip-address '172.31.10.155' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan api --a-ip-address '172.31.10.240' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan api-int --a-ip-address '172.31.10.240' --a-create-reverse  
 [archy@ipa03 ~]$ ipa dnsrecord-add okd.archyslife.lan '*.apps' --a-ip-address '172.31.10.240' --a-create-reverse

Let's verify everything has been added accordingly:

 [archy@ipa03 ~]$ ipa dnsrecord-find okd.archyslife.lan     
  Record name: @  
  NS record: ipa03.archyslife.lan., ipa01.archyslife.lan., ipa02.archyslife.lan.  
  
  Record name: api  
  A record: 172.31.10.240  
  
  Record name: api-int  
  A record: 172.31.10.240  
  
  Record name: *.apps  
  A record: 172.31.10.240  
  
  Record name: bootstrap  
  A record: 172.31.10.150  
  
  Record name: helper01  
  A record: 172.31.10.173  
  
  Record name: helper02  
  A record: 172.31.10.178  
  
  Record name: master01  
  A record: 172.31.10.151  
  
  Record name: master02  
  A record: 172.31.10.152  
  
  Record name: master03  
  A record: 172.31.10.153  
  
  Record name: worker01  
  A record: 172.31.10.154  
  
  Record name: worker02  
  A record: 172.31.10.155  
 -----------------------------  
 Number of entries returned 12  
 -----------------------------

Everything looks expected, so no futher modifications are necessary. Now continue with the DHCP Setup.

Feel free to commend and / or suggest a topic.

Comments

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