Jira and Github bi-directional issue sync

[Jaden Zerbe]

Hello,

I am looking for a solution that will easily achieve bi-directional syncing of issues between an On-Prem Jira Server and On-Prem GitHub Enterprise both behind a firewall. Most, if not all, plugins that I have found do not support On-Prem behind a firewall. 

I have looked at webhooks and that is a potential solution. However, I would prefer a solution that does not require any in-house development if possible. If anyone has had any luck in a similar situation, I would appreciate hearing about the solution that was used.