Hi Nicolash-q,
I dont think ,half opened connections can be kept on the SRX.it will drop it within few seconds.
But as a work around , you can use selective packet mode for that traffic using firewall filter:
Using this technique, you can use both packet mode for this stream and flow mode for rest.
set firewall filter PACKET-MODE term 1 from source-address X.X.X.X/32
set firewall filter PACKET-MODE term 1 from destination-address y.y.y.y/32
set firewall filter PACKET-MODE term 1 then packet-mode
set firewall filter PACKET-MODE term 2 then accept
Now apply the filter PACKET-MODE in required interface in inbound or outbound direction.
So traffic coming from particular source address of X.X.X.X/32 will only be processed as packet mode by SRX, rest will be processed as flow mode.
Regards
rparthi
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