17 October 2022 at 4:11:00 AM GMT+00:00Investigating Problem :
Switching Email Server
Identified Problem :
To update the nameservers provided by us in domain DNS settings; after that, it will take up to 48-78 hours for complete propagation, that period which will take to complete the resolution of IP with the DNS record is considered as DNS propagation time.
In technical terms, every ISP maintains a DNS cache, which stores the data of domain-level DNS records. When you update any new DNS record for the domain name, it has to be updated to the ISP so that the request will be served through the new record. Every ISP has a different TTL (Time To Live) period; depending on that, they refresh the DNS cache. DNS Server is handling this request. Some DNS servers will update the cache within 15 minutes, or some take up to 78 hours; hence, we as a host always recommend our customers wait up to 48-78 hours for the complete propagation.
Solving Problem :
Why does DNS propagation take too much time? DNS propagation delay can happen due to two reasons. Name server changes at your registrar. DNS caching due to TTL value set up in resource records. We have very little control over the first case as any changes done at the registrar may take 24 to 48 hours to propagate on Internet (though it’s generally nowhere near this long). We can manage the downtime of the site in the second case.
To reduce the DNS lookup overhead, every name server cache the DNS records fetched at a time. The time for which these values remain in the cache is controlled by the TTL (Time to Live) value set in these resource records. For example, if the A record of the site has a TTL value, say 14400 seconds (4 hours), then this result will stay in the DNS cache for 4 hours once fetched from the authoritative name servers. If the IP address of this site is changed in between, the name server which caches the previous result will not be able to see this change as it is still fetching the details from its local cache.
Affected Components :
Major Platform Endpoint and E-mail communication
Not-Affected Components :
E-mail Notification communication
