Norton ConnectSafe, used to provide a free adult, malware, and phishing filtered DNS service. I have young kids, so this makes “parental control” easier. However they discontinued this service in 2018. I believe Cisco bought it, stripped it and used parts of it in a pay per use service.
I have started using Cleanbrowsing, even though its not recommended by ipFire. This is not because it is bad, but rather a legal disclaimer as they do modify your DNS requests. The modifying part being filtering. They have 3 different services, all free. Good for a small household. Have not found anything wrong with it… yet.
I was looking into creating a DNS filter for the ipfire, but since the DNS serives has moved to unbound, the scripts I had created stopped working correctly. Using a DNS filtered service for now will have to do.
The following is my opinion, so I suggest to do additional research to validate it.
A service provider to avoid like the plague is DNSReactor. Their services seem to have been hijacked for a few months now and they have not bothered fixing it. Which means they either a) don’t know or b) don’t care. Both would indicate a lack of ethics, and should sound alarm bells.
Greenteam is an Israeli based service, and if credible sources are to be believed, they are affiliated to a certain intelligence community. Again tread carefully when using them.
Yandex is Russia based, see my former comments, as they also apply.