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Posts: 12
Joined: Mon Jun 13, 2011 7:36 pm

CRS305 Issues

Fri Feb 14, 2020 8:25 pm

Please forgive me for I have sinned. I was excited for this so I put it in production with very little testing....

I have a setup with a few VM hosts running about 20 vms. The VM hosts have been plugged into a unmanaged 1gb switch passing traffic just fine.
I decided to play around with some 10g gear so I picked up a mikrotik crs305-1g-4s+ and some 10Gb PCI-E NICs. I settled on 10G SFP+ DAC cables for the closer servers and a chunk of fiber with 10GBASE-SR Module for Mikrotik S+85DLC03D for longer run. I ended up using an additional mikrotik crs305-1g-4s+ on the end of the fiber run so I could have more 10G ports to play with.
At this point all the youtube videos that I've seen say that everything should just work.
I run a udp speedtest from the first mikrotik crs305-1g-4s+ (lets call it mikrotik A) to the other mikrotik crs305-1g-4s+ (mikrotik B) across the fiber link and I see about 950Mbps. Here's my stats for the link on mikrotik A.
/interface ethernet monitor sfp-sfpplus1
                      name: sfp-sfpplus1
                    status: link-ok
          auto-negotiation: done
                      rate: 10Gbps
               full-duplex: yes
           tx-flow-control: yes
           rx-flow-control: yes
        sfp-module-present: yes
               sfp-rx-loss: no
              sfp-tx-fault: no
                  sfp-type: SFP-or-SFP+
        sfp-connector-type: LC
      sfp-link-length-50um: 80m
      sfp-link-length-62um: 30m
           sfp-vendor-name: Mikrotik
    sfp-vendor-part-number: S+85DLC03D
       sfp-vendor-revision: A
         sfp-vendor-serial: MISSRJ52813
    sfp-manufacturing-date: 14-06-01
            sfp-wavelength: 850nm
           sfp-temperature: 37C
The other issue that I'm having is that mikrotik A doesn't "contain" the traffic like the unmanaged switch did. I now see all the traffic between the VM hosts cross my main router.

I'd appreciate any help...
just joined
Topic Author
Posts: 12
Joined: Mon Jun 13, 2011 7:36 pm

Re: CRS305 Issues

Thu Feb 20, 2020 5:15 pm

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Posts: 114
Joined: Wed Sep 01, 2010 3:52 pm

Re: CRS305 Issues

Fri Mar 13, 2020 12:32 pm

speedtest is not all telling feature. If you want to see if it can go faster try to type in the speed you want (9G for example) and see the real speed on the interface and on the interface of the other mikrotik device. If you send 9Gb/s it is necesery to check if it is also arrived to its destination. Bandwidth test speeeds shownyou can ignore...

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