If you are seeing the error message ‘The Atlassian Marketplace server is not reachable. Available application updates will not appear on this page.” on the Jira Version & License page – https://jira.mycompany.com/plugins/servlet/applications/versions-licenses. Then you should check the following three places:
Make sure your Jira box has a workable network. Run some ping or curl testings to ensure the Jira box can reach the Internet.
For most enterprise, they normally have a corporate proxy in place. If so, you need to add the proxy settings in the Java property settings in setenv.sh file. Here is an example:
-Dhttp.proxyHost=proxy.mycompany.local -Dhttp.proxyPort=8080 -Dhttp.proxyUser=jira -Dhttp.proxyPassword='******' -Dhttp.nonProxyHosts='*.mycompany.com|*.mycompany.local' -Dhttps.proxyHost=proxy.mycompany.local -Dhttps.proxyPort=8080 -Dhttps.proxyUser=jira -Dhttps.proxyPassword='******' -Dhttps.nonProxyHosts='*.mycompany.com|*.mycompany.local'
For most corporate proxy, they intercept the SSL traffics which means they decrypt the SSL traffics then re-encrypt them with its own certificate which is normally issued by internal CA. Jira is a Java application, and Java does not honour the trusted CA in the OS, it has its own trusted CA keystore which by default is /usr/java/default/lib/security/cacerts, default password is changeit. So you can either tell Java to use a different trusted keystore where the internal root CA and intermediate CA certificates are saved or import them into the default trusted keystore. To me, I prefer the second option, as I may need those public root CA as well. To import the Internal CA certificate, here is the sample command:
keytool -import -alias mycompany-internal-ca -keystore cacerts -file mycompany-internal-ca.crt