Currently it is not possible to use Retrace with agent behind proxy and FW without allowing Stackify IP adresses.
We found out and tested that it is possible, when http.proxyHost and http.proxyPort are set for azure library.
Now we have customized linux java agent with http proxy set, which is able to communicate without direct connection to stackify and without any FW allowing rule.
Additionally, it could be great to have an installation script arguments for proxyHost and proxyPort because of failing installation behind proxy. This could set the proxy for azure library too.