In Microsoft Office 365 Dedicated/ITAR (vNext), you receive HTTP status code 503 when you check for near Real-Time Logs (nRTL) to download.
HTTP 503 errors are transient errors that can occur for many reasons.
When you obtain nRTL logs, some 503 errors are expected. You should build your script to re-evaluate any 503 errors. If the errors are frequent and they affect your ability to retrieve logs, contact Microsoft Online Services Support by online submission or by telephone .
Article ID: 3164159 - Last Review: Aug 11, 2016 - Revision: 1
Microsoft Business Productivity Online Dedicated, Microsoft Business Productivity Online Suite Federal