You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

đź’ˇ Did you know?

⏺ If you can't accept iCloud Terms and Conditions... Learn more >

⏺ If you don't see your iCloud notes in the Notes app... Learn more >

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

DNS SERVER Mobile data ridiculous!

I’ve just changed my phone contract to a lower 20gb a month as I’ve never reached. I’m only half way through the month and for the first time the date is flying down due to this DNS.


I reset my data usage at 8am today, mainly been of the WI-FI unless it was going to slow and would flick to mobile data.


from the last 13 hours DNS Server has used the most data, how do I stop this?


iPhone 11 Pro, iOS 15

Posted on Dec 6, 2021 1:37 PM

Reply
3 replies

Dec 6, 2021 1:44 PM in response to Liam9000

Every time you go to a website, update a page in a browser, open an app, change pages in an app, send or receive email, send or receive text, any app updates its database, your phone sends a request to your linked DNS (Domain Name Server) to look up the IP address of the URL. Each of those uses data. 131 MB is not that much data. Probably most of your active usage was on Wi-Fi, but Wi-Fi turns off when the screen locks, so any updates that happen when the screen is locked will use mobile data. What you are observing is low mobile data usage for most other stuff, not high usage for DNS.

Dec 6, 2021 1:59 PM in response to Liam9000

Some apps and web services and websites can keep short timeout values (TTLs) on DNS translations.


These shorter timeouts reduce the efficiency of any caching of DNS translations, and require more translation requests.


But as correctly stated above, every time you access a webpage, you need one and usually many more DNS translations.


That means accessing the local DNS cache, or accessing DNS remotely when the DNS cache has no data or stale data.


Same for apps accessing their backend servers. Those too trigger DNS translations.


Checking security certificates also involves DNS, such as when verifying the certificate presented by a TLS network connection from some local client app or tool to a remote server.

DNS SERVER Mobile data ridiculous!

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.