What should I do if DNS server is not responding?

Related questions

1. How many DNS servers do I need?
2. What are primary and secondary DNS?
3. Is Cloudflare DNS fast?
4. Where do I find my primary DNS?
5. What does Cloudflare DNS do?
6. Where can I find my secondary DNS?
7. Why does my DNS server keep going down?
8. Which is better OpenDNS or Google DNS?
9. What does Cloudflare free do?
10. Do I need a secondary DNS?

Tags

1. #connections
2. #problem
3. #click
4. #right
5. #server
6. #error
7. #change
8. #check
9. #start
10. #helps
11. #changes
12. #network
13. #google
14. #select
15. #internet
16. #responding
17. #settings