Thank Jonathan,
Didn't know that checkUrl.jsp page and this is helpful.
After I tried with two services url, I used to encounter issue
One might be because of cert what you mentioned as it is using local ad cert and setup locally.
And another is slow ogc wms service.
Below is the list of response respectively.
Would like to know where to read the log?, I believe it is not from portal log folder which is configure in arcgis-logsettings.json.
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{ "success": false, "error": {"message": "Http StatusCode: -1, Error checking resource:- https://xxxx/mapserver }
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This service is slow, it took 30secs to response in browser, it is ogc service with token based and it has valid cert as well.
{ "secured": false, "httpStatusCode": 503, "httpStatusMessage": "HTTP/1.1 503 Service Unavailable", "httpResponse": "", "url": "https://wms/ogc url" }
Best Regards,
Than