Bug 1925132

Summary: Instructions for custom DNS setup are not correct - alias reference for CNAME should be prefixed with 'elb.'
Product: OpenShift Container Platform Reporter: Ilya Buziuk <ibuziuk>
Component: DocumentationAssignee: Latha S <lmurthy>
Status: CLOSED WONTFIX QA Contact: Xiaoli Tian <xtian>
Severity: unspecified Docs Contact: Latha S <lmurthy>
Priority: unspecified    
Version: 4.7CC: alkazako, pbergene
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Last Closed: 2022-09-27 16:04:54 UTC Type: Bug
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current instructions for the custom DNS setup none

Description Ilya Buziuk 2021-02-04 13:08:24 UTC
Created attachment 1755064 [details]
current instructions for the custom DNS setup

Created attachment 1755064 [details]
current instructions for the custom DNS setup

Description of problem:


Currently, the instructions for adding the custom domain are the following:

"To use a custom route, you must update your DNS provider by creating a canonical name (CNAME) record. Your CNAME record should point to your custom domain workspaces.openshift.com, to the OpenShift canonical router hostname, apps.sandbox.x8i5.p1.openshiftapps.com, as the alias." see screenshot attached.

However, apps.<clustername>.<clusterid>.<shard>.openshiftapps.com will not  resolve to anything. *.apps.<clustername>.<clusterid>.<shard>.openshiftapps.com is the wildcard entry, so you need something prepending that. 

To align with the way it was on v3 we usually chose the arbitrary string elb, eg elb.apps.<clustername>.<clusterid>.<shard>.openshiftapps.com.  That will hit the routers.

examples of nslookup:

ERROR:

[ibuziuk@fedora ~]$ nslookup apps.sandbox.x8i5.p1.openshiftapps.com
Server:		127.0.0.1
Address:	127.0.0.1#53

** server can't find apps.sandbox.x8i5.p1.openshiftapps.com: NXDOMAIN


SUCCESS:

[ibuziuk@fedora ~]$ nslookup elb.apps.sandbox.x8i5.p1.openshiftapps.com
Server:		127.0.0.1
Address:	127.0.0.1#53

Non-authoritative answer:
Name:	elb.apps.sandbox.x8i5.p1.openshiftapps.com
Address: 34.195.161.178
Name:	elb.apps.sandbox.x8i5.p1.openshiftapps.com
Address: 34.195.169.86


So the correct OpenShift canonical router hostname should be prefixed with `elb.` in the instructions