monitoring page keeps displaying Monitoring request failed 404

[LeeDr]

Kibana version: 7.10.0

Elasticsearch version: 7.10.0

Server OS version: CentOS 7

Browser version: Chrome 86

Browser OS version: Windows 10

Original install method (e.g. download page, yum, from source, etc.): RPM default dist

Describe the bug: Monitoring is displaying an error dialog Monitoring request failed 404 repeatedly on the screen.

Steps to reproduce:

1. install Elasticsearch and Kibana 7.10.0 default distribution (I'm on latest snapshot build, Trial license, Security enabled)
2. Enable Monitoring self-monitoring

Expected behavior: Should update monitoring data without errors

Screenshots (if relevant):

Errors in browser console (if relevant):
Request URL: https://localhost:5601/api/monitoring/v1/elasticsearch_settings/check/internal_monitoring
Request Method: POST
Status Code: 404 Not Found

Provide logs and/or server output (if relevant):

Oct 28 19:53:51 localhost.localdomain kibana[28026]: {"type":"response","@timestamp":"2020-10-28T19:53:51Z","tags":[],"pid":28026,"method":"post","statusCode":200,"req":{"url":"/api/monitoring/v1/alert/Foek2FuXQAKJmnd9ioKlIw/status","method":"post","headers":{"host":"localhost:5601","connection":"keep-alive","content-length":"55","kbn-version":"7.10.0-SNAPSHOT","user-agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","content-type":"application/json","accept":"*/*","origin":"https://localhost:5601","sec-fetch-site":"same-origin","sec-fetch-mode":"cors","sec-fetch-dest":"empty","referer":"https://localhost:5601/app/monitoring","accept-encoding":"gzip, deflate, br","accept-language":"en-US,en;q=0.9"},"remoteAddress":"10.0.2.2","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","referer":"https://localhost:5601/app/monitoring"},"res":{"statusCode":200,"responseTime":377,"contentLength":9},"message":"POST /api/monitoring/v1/alert/Foek2FuXQAKJmnd9ioKlIw/status 200 377ms - 9.0B"}$

Oct 28 19:53:51 localhost.localdomain kibana[28026]: {"type":"response","@timestamp":"2020-10-28T19:53:51Z","tags":[],"pid":28026,"method":"post","statusCode":200,"req":{"url":"/api/monitoring/v1/clusters/Foek2FuXQAKJmnd9ioKlIw","method":"post","headers":{"host":"localhost:5601","connection":"keep-alive","content-length":"101","accept":"application/json, text/plain, */*","kbn-version":"7.10.0-SNAPSHOT","user-agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","content-type":"application/json;charset=UTF-8","origin":"https://localhost:5601","sec-fetch-site":"same-origin","sec-fetch-mode":"cors","sec-fetch-dest":"empty","referer":"https://localhost:5601/app/monitoring","accept-encoding":"gzip, deflate, br","accept-language":"en-US,en;q=0.9"},"remoteAddress":"10.0.2.2","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","referer":"https://localhost:5601/app/monitoring"},"res":{"statusCode":200,"responseTime":392,"contentLength":9},"message":"POST /api/monitoring/v1/clusters/Foek2FuXQAKJmnd9ioKlIw 200 392ms - 9.0B"}$

Oct 28 19:53:52 localhost.localdomain kibana[28026]: {"type":"response","@timestamp":"2020-10-28T19:53:52Z","tags":[],"pid":28026,"method":"post","statusCode":404,"req":{"url":"/api/monitoring/v1/elasticsearch_settings/check/internal_monitoring","method":"post","headers":{"host":"localhost:5601","connection":"keep-alive","content-length":"2","accept":"application/json, text/plain, */*","kbn-version":"7.10.0-SNAPSHOT","user-agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","content-type":"application/json;charset=UTF-8","origin":"https://localhost:5601","sec-fetch-site":"same-origin","sec-fetch-mode":"cors","sec-fetch-dest":"empty","referer":"https://localhost:5601/app/monitoring","accept-encoding":"gzip, deflate, br","accept-language":"en-US,en;q=0.9"},"remoteAddress":"10.0.2.2","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","referer":"https://localhost:5601/app/monitoring"},"res":{"statusCode":404,"responseTime":26,"contentLength":9},"message":"POST /api/monitoring/v1/elasticsearch_settings/check/internal_monitoring 404 26ms - 9.0B"}$

Oct 28 19:53:52 localhost.localdomain kibana[28026]: {"type":"response","@timestamp":"2020-10-28T19:53:52Z","tags":[],"pid":28026,"method":"post","statusCode":200,"req":{"url":"/api/monitoring/v1/alerts/enable","method":"post","headers":{"host":"localhost:5601","connection":"keep-alive","content-length":"2","accept":"application/json, text/plain, */*","kbn-version":"7.10.0-SNAPSHOT","user-agent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","content-type":"application/json;charset=UTF-8","origin":"https://localhost:5601","sec-fetch-site":"same-origin","sec-fetch-mode":"cors","sec-fetch-dest":"empty","referer":"https://localhost:5601/app/monitoring","accept-encoding":"gzip, deflate, br","accept-language":"en-US,en;q=0.9"},"remoteAddress":"10.0.2.2","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.111 Safari/537.36","referer":"https://localhost:5601/app/monitoring"},"res":{"statusCode":200,"responseTime":465,"contentLength":9},"message":"POST /api/monitoring/v1/alerts/enable 200 465ms - 9.0B"}$

Oct 28 19:53:59 localhost.localdomain kibana[28026]: {"type":"log","@timestamp":"2020-10-28T19:53:59Z","tags":["debug","plugins","usageCollection","collector-set"],"pid":28026,"message":"not sending [kibana_settings] monitoring document because [undefined] is null or invalid."}$

Any additional context:

[elasticmachine]

Pinging @elastic/stack-monitoring (Team:Monitoring)

[igoristic]

Thanks for filing the ticket!

This should be resolved by the following backport: #81955, but feel free to open it if the issue still persists