Dns sur iPad

Bonjour,
Depuis quelques jours et par intermittences je ne peux ouvrir certaines pages sur safari,Google.
La page affiche ceci:

Hold on!
You have reached this web page because you (or your network administrator) are using one or more of the old OpenNIC Tier2 DNS Resolvers which is/are not supported or not actively maintained anymore and as such will be shut down soon.

We're trying to keep the amount of such events (IP changes, soon-to-be shut down servers, etc.) very low but since OpenNIC and many Tier2 Providers are non-profit organizations or normal people, this unfortunately happens every now and then and cannot be prevented.

Please take a look at "DNS Servers near you" below to find a new DNS resolver near you that you can use from now on and make sure to subscribe to the OpenNIC discuss mailing list in order to stay up to date with the available DNS resolvers and receive update information regarding planned maintenance and similar information.

Je n'ai aucune idée de la marche à suivre pour rectifier cela.
Merci pour l'aide que vous pourrez m'apporter.