How to update QUICKLY for clients on subdomains.

[Truong Tan Son]

Dear Sir,        

I have trouble about update quickly for clients on subdomains.

Zoom out of my DNS:
----------------------------------------------------------
[domain.com]                is    Root server.
[sub1.domain.com]        is    Subdomain.
[sub2.domain.com]        is    Subdomain.

                        [domain.com]
                        /                        \        
                       /                          \    
[sub1.domain.com]                    [sub2.domain.com]
-----------------------------------------------------------

After change some records of [sub1.domain.com],
and reload [sub1.domain.com], after that, clients of [sub2.domain.com] CAN NOT see the new records, it still use old records.

It only takes effect if I reload all servers.

Default, $TTL is 3600 for all servers.

Please help me how to update quickly for clients after change something on servers.


Thanks,
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