What is the filtering DNS on a Skie device and can students change it?
The filtering DNS is a DNS service that refuses to resolve unsafe domains, and Skie locks it on the device so it applies to every app and browser. Students cannot change it, because the Private DNS setting is blocked and re-applied. It is on by default for every managed device.
DNS is the lookup step that turns a website name into an address. A filtering DNS answers normally for safe sites and refuses for categories such as adult content. Because every app uses DNS, filtering there covers the browser, in-app web views and any app that opens a link.
Skie sets the filtering DNS as the device's Private DNS, using encrypted DNS to reach the filter, and then blocks the Private DNS setting in Android so the student cannot edit it. If the setting were somehow changed, Skie re-applies the protection. Chrome's own secure DNS is turned off so the browser does not pick a separate resolver.
The filter is chosen by the organisation. Organisations without their own use the default, and a group can have a different one. The owner curates a list of available filters and organisation admins choose from it. See the entries on the default filter and on organisation filters for how selection works.
Because the DNS is configured on the device and not on the network, it works at the school gate and at home. That is the reason the filter travels with the device on any Wi-Fi or mobile data connection.
A condition to know about: some networks block the port used for encrypted DNS. In that case the device uses the network's DNS and the dashboard flags it, so you know where to fix the network. Run the network check wizard before rollout.