I'm confused. The lookup is for the localhost, so how would this alter failover mechanisms? You don't want a lookup for the localhost being responded to with an address of a different data centre surely?
It's not for localhost, it's for the server name. While Gitlab and Teamcity normally are on the same box, they can operate on different boxes or in different data centers. It's looking up a DNS name which happens to point at the same box...does that explain it more clearly?
