2

It occurs to me, that hosting a website on www.domain.com will result in duplicate, unnecessary DNS lookups if www is a CNAME and not an A(AAA) Record. If the CNAME points to another CNAME, things start getting messy.

WWW as an A Record: one lookup for the A record

WWW as a CNAME: one lookup for the CNAME, plus (at least) one for A record.

For the purposes of SEO, for which which speed is a measure, will this matter? Should I change all my CNAMEs to A records?

|improve this question
2

This doesn’t matter at all in respect to SEO. SEO means having a site that is user friendly (speed, ui/ux), content that matters to a user depending on intent and lastly but most importantly - a product or service with demand.

|improve this answer
  • If you are concerned about user centric performance management - take a look at the RAIL model. Have code splitting in place (webpack 4), have a local server or cloudfalte If you go national, reduce js dependencies and take advantage of lazy loading wherever possible. That always does the trick. We run a successful site for £60 per month hosting - just by optimising delivery we turned super competitive ... nevermind Tecord Type – Georg Keferböck Jul 19 at 10:25
  • Some will argue that about speed an A record is better than a CNAME because of less resolutions... which is not really a problem in fact due to caching and CDNs use CNAME extensively. A local IP (hence CDNs, anycast, etc.) matters probably more. – Patrick Mevzek Jul 19 at 14:33
  • Hmmm ... A record is just as fast as a CNAME record when they're within the same domain, e.g. CNAME (example.com) points to A record (example.com), while a CNAME of cdn.example.com that points to a different domain like yoursite.cloudfront.net would incur an extra lookup and thus be slower. (Should add, that this is what my engineer just said - don't shoot the messenger!). – Georg Keferböck Jul 19 at 16:32
  • 1
    Technically true, but when you use CNAME it is "often" because you need to point to an external provider (often a CDN), hence different zones. If you manage both parts, then you could indeed eliminate the CNAME altogether in the zone by fixing the provisioning of it. Look at www.microsoft.com for example: 3 CNAME, 4 separate zones. – Patrick Mevzek Jul 19 at 16:51
  • @PatrickMevzek True and worth a thumbs up ;) – Georg Keferböck Jul 19 at 17:42

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.