Current status: We’ve completed our deployment of domain controllers and we’re performing our final validation tests to ensure all systems are functioning as expected.
Updated: 2019-01-28 04:45 (UTC)
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Current status: We’ve determined that excessive load is causing queues within the authentication infrastructure. We’re formulating a plan to remediate impact.
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Current status: We’ve determined that there is higher than expected queuing within the authentication infrastructure, which may be the cause of impact. We’re working to identify the cause of these queues and determine steps to remediate impact.
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Current status: We’re gathering detailed forensics within the affected infrastructure to isolate the cause of the connection time outs and identify steps to remediate impact.
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Current status: Our telemetry data is indicating connection time outs within the Exchange authentication infrastructure, resulting in impact to the service. We’re looking into the Domain Controller logs to understand the cause and remediate impact. Scope of impact: Impact is specific to users who are served through the affected infrastructure.
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Current status: We’ve confirmed that the queued email has been successfully processed. We will continue monitoring the service throughout the business day to ensure the service continues to operate normally.
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User Impact: Users are unable to connect to the Exchange Online service via multiple protocols. As a result of this issue, users are receiving an error message indicating the number of concurrent connections has exceeded a limit when they attempt to send and receive email.
Current status: We’ve determined that a subset of Domain Controller infrastructure is unresponsive, which is resulting in user connection time outs. We’re optimising connectivity to the healthy infrastructure while fixing the unhealthy Domain Controllers.
Scope of impact: Impact is specific to users who are served through the affected infrastructure.
Start time: Thursday, January 24, 2019, at 9:00 AM UTC
Preliminary root cause: Previously, a subset of our managed Domain Controllers were in a degraded state, affecting Exchange Online functionality.