Hi to all,
My topology is the following:
RB493AH---Ether1----Microwave Gateway---VLANS 1, 3, 5-----Microwave Gateway---Ether1---RB493AH
I create 802.1q vlans on ether 1 and i send these vlans over a microwave device . Everything works OK (all VLANs pass correclty over the microwave link) , but there is one issue.
The management IP of the Microwave device is part of vlan 3 and there is an option in the microwave device that the ethernet frames going to this management IP can be tagged.
Everything fine so far. I can ping the management IP of the microwave device that is tagged to vlan3. The problems start when i move this configuration from Ether1 and going to another ethernet interface of the Mikrotik (for example Ether2) , then the management IP of the microwave is not accessible any more.
The only difference i found so far is the L2MTU which is 1526 for eth1 and 1522 for all other ethernet interfaces.
I tried changing it but it was not possible.
How could these four bytes affect that? I do not use QinQ or MPLS or VPLS, only 802.1q VLANS.
[admin@mikrotik] > interface print
Flags: D - dynamic, X - disabled, R - running, S - slave
# NAME TYPE MTU L2MTU
0 ether1 ether 1500 1526
1 ether2 ether 1500 1522
2 ether3 ether 1400 1522
3 ether4 ether 1500 1522
4 ether5 ether 1500 1522
5 ether6 ether 1500 1522
6 ether7 ether 1500 1522
7 ether8 ether 1500 1522
8 R ether9 ether 1500 1522