KB450216 – Jumbo Frames
Posted on March 23, 2020 by Archie Blanchard
Understanding the advantages and use case of Jumbo frames.
- A network with end-point devices which support Jumbo frames.
- Network routing devices with Jumbo frame support.
- A LAN(local area network) which supports at least 1 Gbps.
What is a Jumbo frame?
- An Ethernet frame which exceeds 1,500 MTU (maximum transmission unit).
- 1,500 MTU is equivalent to 1,500 bytes.
- A jumbo frame exceeds this 1500 MTU, and is typically set to 9,000 MTU.
- A larger packet means less overall traffic and processing required for a network and end-devices.
How do I make proper use of Jumbo frames?
- Your end-point and network devices will all need to support jumbo frames.
- A dedicated VLAN compatible with jumbo frames.
- All devices involved will need their MTU configured to 9,000.
- Any MTU mismatches will result in packet loss.
Why use Jumbo frames? Why not?
- Jumbo frames improve network performance. Mileage will vary, and will likely only be a marginal increase.
- Useful for lowering the stress put on the CPU and network.
- Larger frames being transmitted means less overall traffic that needs to be processed and exchanged over a network.
- If jumbo frames are sent to devices that do not support jumbo frames, there will be immediate and substantial packet loss.
- Likewise, if a single device on the jumbo frame network does not support jumbo frames, there will be packet loss and potentially other network errors.
- The amount of time it may take to set up Jumbo frames for a large-scale network can be very time consuming.
- Each and every device must be configured properly to support the use of this feature.
To verify that you’ve configured jumbo frames correctly, we would advise benchmarking your transfer speeds before and after the initial setup. While it’s likely there will be an increase in performance, it’s also likely that increase will only be marginal.