Session based packet mirroring in a network asic

A forwarding engine comprising a circuit configured to:

• receive a mirror bit mask vector including a plurality of bits and associated with a packet;
• and
• for each bit of the bits:
• determine when conditions for a mirror session for the bit are met based on the packet;
• and
• when the conditions for the mirror session for the bit are met, set a value of the bit to a mirroring value that indicates that mirroring is desired for the packet for the mirror session.

A network chip comprising:

• a forwarding engine configured to:
• receive a packet, wherein the packet is associated with a mirror bit mask vector including a plurality of bits;
• and
• when the forwarding engine determines that conditions for a mirror session for a bit of the plurality of bits are met by the packet, set a value of the bit to a mirroring value that indicates that mirroring is desired for the packet for the mirror session;
• and
• a multicast replication engine coupled with the forwarding engine, wherein the multicast replication engine mirrors the packet according to the mirror bit mask vector.

A method of implementing a forwarding pipeline, the method comprising:

• receiving a packet and a mirror bit mask vector including a plurality of bits with the forwarding pipeline;
• determining with the forwarding pipeline that conditions for a mirror session for a bit of the plurality of bits are met by the packet;
• setting a value of the bit to a mirroring value that indicates that mirroring is desired for the packet for the mirror session;
• mirroring the packet with a multicast replication engine based on the mirror bit mask vector.