MX record cutover checklist
Overview
Wrong MX loses mail silently—treat as change of the highest risk class.
Pre-check
Lower TTL 24–48h ahead; verify SPF/DKIM/DMARC for new gateway ready.
Cut steps
- Flip MX to new priority hosts.
- Keep old gateway journal/forward short period for stragglers if architecture permits.
- Monitor queues both sides first 4 hours live.
Rollback
Document previous MX set in ticket for instant DNS revert.
Sign-off
Business owner acknowledges possible 15–30 minute graymail during propagation.
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