Hello everyone.
I have a question about the handling of packets after redirection. Hope to get your help, thanks in advance.
I now have a requirement that routeros redirect some packets to the sub-router, and then return to routeros for normal forwarding after re-redirection through the program of the sub-router. (In simple terms, it has been processed twice by dst-nat, the first time is to divert traffic to the secondary route, and the second time is to redirect to the correct node)
My current solution is to perform src-nat at the same time when redirecting through secondary routing. Then restrict the source address in the secondary route (that is, the address of src-nat) in the mangle policy. This can avoid network storms caused by repeated redirection of a packet.
However, this will cause meaningless multiple forwarding of packets when they return (path: main route network exit > secondary route srcnat address > source address), and cause a large number of tcp retransmission packets, affecting network quality.
Now I want to avoid the src-nat behavior of the secondary route, and let the main route automatically release the redirected packets. I try to use packer mark to avoid repeated redirection, but it seems that the packer mark disappears after being processed by the secondary route.
Is there any way to mark the traffic. Let these processed traffic be forwarded directly instead of being captured by mangle and redirected repeatedly?
Your help is greatly appreciated, thank you all! 
best wishes!