Hi MFB,
You have 2 options.
1. Firewall filter and Packet mode (your solution) ( flow mode needs return connections to match if not then sessions will be removed)
2, Configure verify specifc static route on the server side route pointing to SRX interface for the client network .
so that return packets are sent to SRX ,in this way , both client to server and server to client connections work flawlessly.
In current situation , since you do not access to remote router for configuring route , your solution is the best option
Regards,
rparthi
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