How do mail filters cache DNS data for spam analysis?
Filter DNS caching behavior:
Why filters cache:
Processing millions of messages
Same DNS lookups repeated constantly
Caching improves performance
Cache duration:
May follow TTL
May use internal cache policies
Some cache longer for efficiency
Implications:
SPF/DKIM changes may not take effect immediately at all receivers
Reputation data may lag DNS changes
Blocklist removal may take time to propagate
Planning:
Allow time after authentication changes before expecting full effect
Do not assume instant propagation
Port authorities may use their own record copies. Updates take time to reach all offices.
Was this answer helpful?
Thanks for your feedback!