A 504 Gateway Time-out usually indicates that the web server or reverse proxy isn't receiving a timely response from the Maximo application server. Since you're running Maximo 7.6.1.0 on Linux, I'd start by checking the application server logs, web server timeout settings, database performance, and overall server resource usage (CPU, memory, and disk I/O). It's also worth verifying whether the issue occurs only with the Service Request module or across other applications.
If the problem is intermittent, there could be a long-running query or a network communication delay between the web server and the Maximo application server.
We encountered a similar timeout issue while integrating an enterprise SMS Gateway Solution with a business application. Increasing the gateway timeout, optimising backend processing, and reviewing server logs helped identify the bottleneck. Looking at your proxy and application server timeout configurations may help pinpoint the root cause.
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John Raugh
100Coins
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