When the SFC Nitrogen project migrated to Karaf 4, we no longer get flows with Nicira NSH (Network Service Headers) Extensions. Previous to migrating to Karaf 4 in Nitrogen, we got all the expected flows.

Here are the LOG messages I get with Serializer Warnings:
https://pastebin.com/F8cWi0xW

Here are the only flows I get now:

$ sudo ovs-ofctl -O OpenFlow13 dump-flows br-int
OFPST_FLOW reply (OF1.3) (xid=0x2):
cookie=0x14, duration=14.070s, table=0, n_packets=0, n_bytes=0, priority=5 actions=goto_table:1
cookie=0x14, duration=14.070s, table=1, n_packets=0, n_bytes=0, priority=300,udp,nw_dst=10.0.0.10,tp_dst=6633 actions=output:0
cookie=0x14, duration=14.070s, table=1, n_packets=0, n_bytes=0, priority=300,udp,in_port=0,tp_dst=6633 actions=LOCAL
cookie=0x14, duration=14.070s, table=1, n_packets=0, n_bytes=0, priority=5 actions=drop
cookie=0x14, duration=14.070s, table=1, n_packets=0, n_bytes=0, priority=250 actions=goto_table:4
cookie=0x14, duration=14.070s, table=2, n_packets=0, n_bytes=0, priority=5 actions=goto_table:3
cookie=0x14, duration=14.070s, table=3, n_packets=0, n_bytes=0, priority=5 actions=goto_table:4
cookie=0x14, duration=14.070s, table=4, n_packets=0, n_bytes=0, priority=5 actions=goto_table:10
cookie=0x14, duration=14.070s, table=4, n_packets=0, n_bytes=0, priority=550 actions=goto_table:10
cookie=0x14, duration=14.070s, table=10, n_packets=0, n_bytes=0, priority=5 actions=drop
cookie=0xba5eba1100000102, duration=14.070s, table=10, n_packets=0, n_bytes=0, priority=660 actions=IN_PORT
cookie=0xba5eba1100000103, duration=14.070s, table=10, n_packets=0, n_bytes=0, priority=650 actions=output:1
cookie=0xba5eba1100000101, duration=14.070s, table=10, n_packets=0, n_bytes=0, priority=655,in_port=1 actions=IN_PORT

As mentioned above, previous to the migration, we were able to create the Nicira NSH flows as expected. Here are the flows we're expecting:
https://pastebin.com/QxYaL6jz

Regards,

Brady