Previous incidents

We have rotated in a new set of sending IPs, and we're seeing Microsoft deliverability rates return to normal. We will continue monitoring this over the coming days.

PostMortem: OVH DNS Outage

Issue Summary:
DNS resolvers on our OVH data center provider went down. Our mail sending infrastructure was unable to pull new mail tasks from the queue, and unable to deliver them due to inability to lookup MX records.

Timeline:
7/14/2025
17:54 [Downtime Begins] OVH DNS Outage, Cargo cannot pull messages off SQS queue, the few messages it has cannot be delivered because it cannot lookup MX records
18:01 [First Alert] BetterStack pings Matthew for "Gmail Deliverab...

We have rotated out affected sending IPs, and microsoft deliverability is returning to normal.