Curious if you know why Upload bandwidth is not stable in 10Gbps

[gatsbylee]

Hello,

I am not sure if there are any other users who have the similar experiences like I have.

First, these are the network gears I have.
- UDM SE ( IPS / IDP are disabled )
- Ubiquity SFP+ to RJ45 Transceiver ( MG model )
- QNAP QNA-T310G1S Thunderbolt 3 to 10GbE Adaptor
- DAC 10Gtek SFP+ DAC Twinax Cable

( The device running bandwidth testing and the WAN is on the same VLAN to remove the overload factor in the crossing VLANs )

I have been using 2.5Gbps WAN ( RJ45 ) since I started using Sonic Internet's 10Gbps Fiber Optic.
It's been stable and worked well.

Recently, I purchased the "Ubiquity SFP+ to RJ45 Transceiver ( MG model )".
And, I connected it to SFP+ port on UDM SE. ( with WAN configuration )

When I wrote about the upgrade on Mediam.com, I ran several bandwidth testing.
( https://medium.com/@life-is-short-so-en ... a97e868384 )
The download bandwidth testing was pretty stable with 8000Mbps on every runs.

However, the upload bandwidth testing wasn't stable.
Sometimes, it got even worse than 2.5Gbps.
Many times, the upload bandwidth got to 1000Mbps or 2000Mbps level.
Or, sometimes, it got to 6000Mbps.

Is there anything I am configuration I am missing, or Sonic's 10Gbps is not stable in terms of Uploading bandwidth?

Thank you
Gatsby

[gatsbylee]

I think I found where the issue is.
It seems the 10GTek SFP+ DAC Passive cable ( 10m ) I bought is not stable with the length.
Based on their doc, if it's longer than 7m ( even on industry official doc ), then the SFP+ DAC Passive cable can't deliver the 10G properly.
( Then, why does the seller even sell the product? )

I tested with a short DAC Passive cable and 10Gbps looks stable.
When I have more updates, I will share with you.