Temporary failure in name resolution isn’t a common issue, it is something that only occurs in events like when you have moved your servers from one host to another and changed the DNS entries and something that needs to be propagated in order to work properly. Or you have played some edits in the DNS entries and changes are not updated in your ISP’s DNS resolver.
Why do I see temporary failure in name resolution?
Because the server is unable to resolve the domain name for you because any recent changes aren’t refreshed for the server’s own offered resolver. You could see this error while upgrading server, ping, traceroute domain name, or any domain-server based queries.
A “DNS Propagation” may take from 5 minutes to 24-48 hours maximum. You can tweak the time-to-live values in order to refresh it faster or slower.
If you did something like above then there is nothing to worry about, it will start working in 24 or max 48 hours once all the changed entries are propagated globally. Just make sure you have edited the correct entries like A, AAAA, CNAME, NS, and similar records.
Directly accessing the services under propagation time may not be easy. But you can forcefully use it by changing the host or resolve file which is responsible for localhost management.
You can either add domains entry locally in host file or switch to a faster resolver using any Public DNS like Google’s (184.108.40.206, 220.127.116.11) or CloudFlare’s (18.104.22.168, 22.214.171.124).
If you often change your DNS records, better set shorter TTL (Time-to-Live) time, this way your changes will reflect faster and you don’t have to rely on any such hacks.
At last, if the issue exists even after waiting 24-48 hours and still it is not getting fixed, that means you have some serious issue from your domain registry. You can only contact your domain provider in such cases, only they can help you in this case.