How long do changes to domain "A" record take?
If I have server and a domain and I rebuild that server and update its domain's "A" record with the new IP address, approximately how long will it take before I will see the new IP address when I run "dig <mydomain>.com"? I've seen information that says it could take 15 minutes and other information that says it could take up to twenty-four hours. Thanks!</mydomain>
3 Replies
Too long :(
Up to 30 minutes, according to https://www.linode.com/docs/platform/manager/dns-manager/#edit-dns-records
rdaniels
Linode Staff
DNS propagation for our name servers is typically up to 30 minutes. However, propagation across the all name servers may take up to 48 hours to fully propagate- although, it may happen in a few hours.
You can check the propagation by using the below command:
dig +trace www.example.com
More precisely, the time it takes for a client to see a change in your DNS records depends first on how fast the change you do in a config file, API or web GUI is reflected on your authoritative servers. Linode claims this takes typically up to 30 minutes.
After that happens, caching DNS resolvers, the client may be using, can cache the old values for the duration of the TTL - in case of changing a record it's the TTL of the (old) record and in case of adding a new record to the zone it's the "min TTL" value of the zone's SOA record. So after this time has elapsed you can be pretty sure the clients are seeing your updated values.
This is governed by the applicable RFCs. It may happen that there is an odd DNS resolver that chooses to ignore the standards, but that is rare and mostly happens only when you use TTL values close to 0 seconds, they tend to have a minimum TTL under which they refuse to go.