I’m running 2 of these in a failover environment - both have the same CPU usage.
No Bridges
No VLANs
Just simple /30 subnets and route rules.
These switches are single-purpose to connect the FOC ( Failover Cluster ) to the SAN
I’m running Mellanox ConnectX-4 Lx Cards on the SAN and Servers
I’m using FS Q-4S28PC02 cables
This issue occurs mostly with large file transfers - but the CPU stays elevated most of the time.
The Speed rarely goes above 2500Mbps
I’m running iSCSI LUNs to the FOC and have most of the utilization in a Cluster Shared Volume ( CSVS ) The max transfer speed I can get in the CSVS is about 120MBps
the LUNs give me about 1.6GBps this seems good - but I’m wondering if my overall system performance is related to the CPU being nearly pegged out constantly.
You need a single vlan aware bridge to take advantage the switch chip and activate L3 hardware offload if you need intervlan routing, remember CRS is geared toward a switch with limited routing capability
This is a great guide
https://www.youtube.com/watch?v=c2sAA6jMjCY
Mikrotik is very verbose compare to any other L3 switch in the market, I know it’s confusing at first
Sorry for the long delay - I needed time to finish some projects and test this. This was a perfect fix. My CSV transfer rate was 256+Mbps ( easily doubled ) and I haven’t tried direct LUN but my CPU stayed under 35% during the transfer.
Also, the video you sent me helped me understand MikroTik’s VLAN logic and utilization ( which I had done wrong before this video ).
So, double thank you - because you helped me see how to implement VLAN and Layer-3 networking correctly - which I have wanted to explore anyway.
