Probably. If you are a resolver and each client caches the DNS for 5 minutes and you have 300 people constantly accessing a certain domain, you have to make 1 r

Probably. If you are a resolver and each client caches the DNS for 5 minutes and you have 300 people constantly accessing a certain domain, you have to make 1 request upstream every second. However, if you cache it for 5 minutes yourself, you only have to make 1 request every 5 minutes. Actually, even if you had a single client, it may still be the case that their caching preferences differ from yours, assuming that either of you are willing to disregard the actual record TTL.