Switch CRS317 cuts off C-tag in qinq packets:
the switch receives a packet with two labels (S-tag & C-tag), but passes only with one label (S-tag).
qinq packets must pass between ports t01 and t02 with S-tag 11.
example config:
/interface bridge
add name=bridge1 protocol-mode=none vlan-filtering=yes
/interface ethernet
set [ find default-name=sfp-sfpplus1 ] l2mtu=9092 mtu=9000 name=t01
set [ find default-name=sfp-sfpplus2 ] l2mtu=9092 mtu=9000 name=t02
/interface bridge port
add bridge=bridge1 ingress-filtering=yes interface=t01 pvid=17
add bridge=bridge1 ingress-filtering=yes interface=t02 pvid=27
/interface bridge vlan
add bridge=bridge1 tagged=t01,t02 vlan-ids=11
/system package update print
channel: current
installed-version: 6.42.1