Network speed reduced if I connect new device to Port on MX

[APredit]

Hello all. 

I have Streaming Encoder connected directly to MX100. I assigned static IP to it and everything works well. This encoder also sits alone from the rest of the network on one VLAN. When I run Speed Test from encoder to the Internet, I am getting 30 Mbps which is good enough for streaming.

I disconnected it and connected New encoder to the same port. I assigned static IP to it in the Meraki portal, but this encoder does not get the same network speed as the old one. It only shows 786 Kbps. It is getting extremely low network connection.

When I disconnected it and plug back in the old one, I am getting again the same fast speed. Can you please advise?

I don't think that the issue is with the encoder, because when I plug it in other location location, I am getting a fast speed test results.

[BrandonS]

That sounds like it could be a duplex mismatch.  

Try going to the local status page on the MX and login to set the port to 100-Full to see if it resolves.  I suppose you ruled out the cable from the device to the MX also?

[BrandonS]

I see Meraki wrote something about the topic that might be helpful too: https://documentation.meraki.com/General_Administration/Tools_and_Troubleshooting/Duplex_mismatches_...

[APredit]

Thanks BrandonS. 

I switched to Full Duplex (it was on Half because of Auto), but it didn't help. 

Yes, I tried connecting directly to a port on the MX excluding a patch panel. Same results, so the issue is not with a cable. 

I assume, if you setup VLAN for a certain port, you cannot connect client devices to it, you have to connect the switch to that port on MX and then your clients to that switch. I am going to give it a try and let you know. 

[PhilipDAth · Accepted solution]

I would use auto speed/duplex on both devices ports.

Have you got any group policy applied to the old encoder?

[APredit]

I switched Port settings Link Negotiation to Auto (10/100/1000Mbps) and everything connected now running at full speed! 

Thank you very much for your help guys!