Redundant L2 and L3 with MLAG and VRRP

RouterOS Beginner Basics
1

Hi there!

I am trying to redesign my Internal Network “semi” redundant: L2 and L3 (for Inter VLAN Routing).
Coming from the Cisco world: Grab a pair of 4500x (for example) setup a VSS and be “pretty much” done with it.
Since the power consumption AND noise of those boxes is pretty insane (for my Home) I`d like to give it a try to do it with MT Devices. I already own 2x CRS317-1G-16S+, 1x CCR2004-1G-12S+2XS and a CRS309.
Internal Network: I do realize there are multiple SPOF in front of the CCR2004, and this is accepted.
Its not a biggie if Internet fails.

The situations I`d like to “survive” are:

  • Firmware Update of either CRS or CCR, so pretty much a Reboot.
  • Failed (broken Device) of either CRS or CCR.

This is what I came up with:
Layer2_3_Redundant.jpg
Not sure how I will configure the CCRs on the WAN side yet, maybe its an option to do VRRP there too: Its a /29 Subnet i received from my ISP. From what i read in other Threads its possible.
There will be Servers that use LACP to connect to both switches, there will be Servers which only use a single Connection to connect to one of the CRS317s.

The Failover-Cluster is somewhat special: They will connect to both switches, but without LACP / Bonding.
They use some proprietary Technology to make that work “switch independently”: Its called Switch Embedded Teaming and its using its own algorithm (Hyper-V Load Balancing) to balance traffic over both links.

What are your Thoughts? Does anybody use a similar setup? What were the challenges implementing it?
Is this setup possible wir ROS7?

  • From what i read: it should.
    MLAG is supported on CRS3xx and VRRP is supported on those CCR2004s.

Kind regards

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The only drawbacks is the NAT - session table doesn’t get sync between the routers - Mikrotik does not have this feature ( HA mode / cluster-mode ),
so the “hitless switchover” not possible, there will be always some “connect/reconnect” event.

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There’s a sync connection tracking available in Mikrotik i think conntrackd is working behind the scene, this is the CARP equivalent in OpenBSD, I’m more willing to be corrected if this was not the case:)