Hi All,
Please can you help with a quick question on running ROS on CRS317 and bridging ports, best practice.
Previous on the CCR routers (EG 1009, 1036) if I have 2 ports I want to connect then I create a bridge and put the 2 ports in. If one needs a VLAN I can create a vlan on the correct port and add that to the bridge simple.
I gather the CRS doesn’t have the horse power for this style of bridging if you want wire speed EG 1gbps in this case.
So on the CRS317 I created 1 bridge (called super-bridge) and then use the VLANS tab under the bridge section to create the various VLANs that are the tagged and untagged to the various ports.
Is this correct? Can I really do the whole switch using one bridge, or should I be creating multiple bridges?
Generally it is advisable to configure single bridge per device as generally only one bridge can offload operations to underlying hardware (you can verify that by executing command /interface bridge port print , HW-offloaded ports show flag ‘H’ in front of port name).
CRS3xx series are sligtly different beasts as they can HW-offload many operations that other devices can not, could well be that single-bridge limitation doesn’t apply either. I don’t have any of CRS3xx so I can’t verify myself, you could …
I wouldn’t use multiple bridges unless those are really needed … for example if I was forced to run two distinct subnets with tagged ports using same VLAN ID … I don’t know if this is possible without multiple bridges. Not that having multiple LANs with same VID is a smart thing to do anyways …
As @Dude2048 explained … single bridge it is. If switching can’t be offloaded, then traffic is handled by CPU which is relatively slow in CRS3xx devices. Not capable of transfer speeds anywhere near wirespeeds. Which means CRS3xx are not really fit for inter-VLAN routing.