USSUP-728 Email2sms SMTP processing delays

Incident Report for 2sms LLC

Postmortem

Start Date: 10/6/2026 11:00pm (EST) / 7th October 2026 03:00 (UTC)

Finish Date: 10/7/2026 2:00am (EST) / 7th October 2026 06:00 (UTC)

Description:

Outage with SMTP traffic acceptance for onward processing

Impacted Services:

  1. SMTP Email2sms

Impacted Customers:

  1. Customers of SMTP Email2sms

Cause:

The mail server mail.2sms.us begun to fail accepting SMTP traffic due to the network load balancer having no healthy nodes to route traffic towards. Automated maintenance restarts of the SMTP service can be triggered when the service levels decline; this is a routine procedure when necessary to maintain performance levels. Services usually reconnect and resolve within less than a second however in this instance due to upstream connection slowness, the relay service did not resume. Ordinarily this would have triggered a backup restart to bring the service back online, however this also did not recover the service.

Detection:

This issue was detected by the next routine automated restart.

Corrective Actions:

Although the eventual resumption of the service was automated, we have already put in place further checks and tooling to more quickly resume services should the primaries fail. We have also identified a fault with our on-call alerting system to address why staff did not receive notification of the issue to manually intervene. We are confident these actions combined will mitigate any reoccurrence.

Preventative actions:

  • Improvements to both internal and external automated monitoring and notification systems
  • Improvements to service availability
  • Improvement to start up procedures for RTO
  • Completion of the Email2sms replacement service

Internal audit:

The security incident has been fed into the ISMS and will be part of the review cycle documents for the January 2027 surveillance audit process.

External audit:

The security incident will be evaluated as part of the review cycle for the January 2027 surveillance audit process.

GDPR:

This incident did not compromise PII (Personally Identifiable Information).

Posted Oct 12, 2026 - 12:21 UTC

Resolved

This incident has been resolved.
Posted Oct 07, 2026 - 07:00 UTC

Investigating

We are currently seeing processing issues for Email2sms SMTP traffic. We are investigating the cause and will update shortly. Traffic sent to our inboxes will be queued and released when the issues are resolved.
Posted Oct 07, 2026 - 04:00 UTC
This incident affected: SMTP.