I try to connect my Bamboo server to my Jira server.
I opened Configure Application Links and put URL to my JIra.
After that I see this message
No response was received from the URL you entered - it may not be valid. Please fix the URL below, if needed, and click Continue.
in Catalina logs I see an exceptions
2020-02-27 11:10:23,187 INFO [http-nio-8085-exec-9] [AccessLogFilter] my_login GET https://bboo.pac.my.com/rest/applinks/3.0/applicationlinkForm/manifest.json?url=https%3A%2F%2Fissues.pac.my.com&_=1582819812547 456315kb
2020-02-27 11:10:23,540 INFO [http-nio-8085-exec-9] [RetryExec] I/O exception (java.net.SocketException) caught when processing request to {tls}->http://bboo.pac.my.com:443->https://issues.pac.my.com:443: Connection reset
I don't know why but the Bamboo use http but the port 443 in log.
I should also said about a proxy. We use netscaler in front of the atlassian boxes