1. Proposed title of this feature request

Use DNS name for callback in assisted service converged flow if available

2. What is the nature and description of the request?

When using ZTP to install SNOs with the assisted service, the Ironic Python Agent (IPA) registers a callback back to the hub cluster using an URL containing an IP address.

 Heartbeat: announcing callback URL https://212.19.81.142:9999 ...

If the hub cluster has a proxy configured, it is likely that the SNO IP address will have to be added to the no_proxy variable of the hub cluster proxy configuration.

We support 3500 SNOs from a single hub, having all those SNO ips in no_proxy can and will be cumbersome as they are often publically routable ips, meaning that they are most likely coming from different CIDRs.

The other alternative is to allow the connection in through the proxy which in most cases is not desirable as the proxy could be in a DMZ.

The idea for this RFE is for IPA to lookup the IP address in DNS using PTR. If there is a PTR record, double check that the FQDN has a A or AAAA record pointing back to the correct IP.

If DNS is valid register the callback using FQDN (pay attention so that the TLS certificate contains the FQDN) instead of IP-address.

The FQDN will more easily be added, as wildcards can be used in no_proxy

3. Why does the customer need this? (List the business requirements here)

Maintaining a huge no_proxy list is cumbersome.

4. List any affected packages or components.

https://github.com/openshift/ironic-agent-image ?