TIL that when setting up download clients for radarr/sonarr/lidarr/readarr/bazarr/prowlarr that you can utilize internal DNS and instead of hardcoding an IP address of your download client server, can use just the CNAME record (ie. instead of 172.10.14.13 I can use transmission.mydomain.com... notice the lact of http(s)://... adding that won't allow the connection to work/
Furthermore, you can use internal DNS to lookup the domain, not the subdomain,
and expose the port, like mydomain.com:7878 for sonarr. This was simpler to
maintain because I don't change which ports an application exposes or utilizes
hardly ever, plus I don't need to maintain CNAME records for every service!