New multisite setup. Domain to be mapped - multisite.ninja - has A record pointed correctly at dedicated IP address of server. Site named instantinfographic.com/multisiteninja has been created and is live.
I go to subsite --> Tools --> Domain Mapping and enter the domain name (multisite.ninja). To the right are options - disabled and entered, directed to mapped, directed to original (I've truncated labels here) - with the second one as the default.
I hit Map Domain, get circle revolving under Health Status column, and then... nothing. Original screen is there again, with no indication of any action. In Network, there are no domains listed as mapped.
I am 99% sure I put sunrise in correct place, I also added entry in wp-config to allow multiple domains per site.
Domain (multisite.ninja) resolves to front page of multisite install so the A record is pointed in the right direction.