Two EoIP tunnels with packet loss

RouterOS General
1

Hi, I am using two EoIP tunnels for service q-in-q vlan and MA vlan over MPLS structure.
In the beginning tunnels work well however I found packet loss occurred recently. The amount is about 2%.
Nothing is changed during this time. I’ve reported to the ISP which provided MPLS structure for me first.
But they test there is no packet loss happened in their structure. So the problem aims back to the both RB450Gx4.
Both EoIP are 1500 mtu, different EoIP tunnel id, same local ip address and remote ip address.
Both bridges are 1500 mtu, and vlan-filtering=yes setting pvid = MA vlan and Service vlan.
The OS version of RB450Gx4 is 6.41.3
Here is my topology.

How can I optimize the EoIP tunnels or bridge in this situation?
Anyone meet the same problem?

Thanks.

2

Bear in mind RB450G max L2MTU is 1520 (see https://wiki.mikrotik.com/wiki/Manual:Maximum_Transmission_Unit_on_RouterBoards#MAC.2FLayer-2.2FL2_MTU).

With MPLS, qinq, EoIP (why EoIP with MPLS and not VPLS?) etc your RB450G L2MTU is falling short and inducing fragmentation… not the ideal device for this kind of application I’m afraid.

3

Thanks for your reply.
There is a mistake which my RouterBoard should be RB450x4. I will edit my post later. Sorry about that.
L2MTU on eoip interface is 65535, bridge is 1594, and ether1~5 are 1598. Should I set L2MTU to 9214 for bridge and interface?
In detail, that MPLS structure is unique. Everything I know that ISP uses half MPLS and half point-to-point.
The main reason to use EoIP is I need to bridge LANs over Internet.
Any better solutions for this situation?

4

Google for
Mikrotik l2tp bcp

5

It seems BCP can not carry Q-in-Q packet.

6

I have discovered that even disabled EoIP interface may cause some tiny glues.

For example, battle.net Blizzard application does not download the games from cloud.

I use 6.46.5