I have 3 MikroTik switches: 2x CRS317 + CRS326, 2 MikroTik routers: CCR1009 and hAP ac², 1 load balancer. Hardware resides in 2 racks and is connected in following manner:
LB --- CRS317 --- | --- CRS317 --- CRS326 --- hAP ac² and CCR1009
| symbol is border between racks. LB has 4 physical gigabit interfaces and due to lack of space in second rack it had to be placed in first one. Because of that I need LB ports to be “directly” exposed in. second rack in CRS326, especially two interfaces that are used for lab setup and their config changes really often. Obviously I don’t want to reconfigure VLANs on all switches along path every time it happens so I want to directly carry traffic along with all VLANs defined on LB to 4 specified ports in CRS326.(two of which are connected to 2 routers so I want it to behave like LB would be connected physically to routers)
According to my understanding of topic this can be done using Q-in-Q. Unfortunately I noticed that it requires changing ether-type on bridge, which, due to limit of 1 HW accelerated bridge, seems to collide with standard VLANs on switches.
However then I noticed VLAN stacking config which seems to use standard 0x8100 ether-type.
So what’s difference between tag stacking (0x8100) and Q-in-Q (0x88a8)? I mean yeah I understand it’s physically encoded in different way and it’s separate standard and that some other switches may only support conventional Q-in-Q with SVID but in this particular scenario (full mikrotik CRS3xx) is there any functional difference between Q-in-Q and CVID stacking (apart from that one method seems to be incompatible with normal VLANs on the same switch)? Are both methods hardware accelerated on CRS3xx?