Intel e1000 ethernet device, change in kernel v3.4, and jumbo frames setting DENIED.
There has been some changes to the driver such that things like checksum verification is offloaded from the CPU. However, this blocks the ability to set a jumbo frame. The kernel does record an error indicating that checksum offloading need be disabled fro jumbo frame MTU sizes to be used. My e1000 interfaces use the 82574L chipset.
1) Was this an intentional change?
2) How do I disable that function so I can set jumbo frames with "ifconfig" or "ip"? I simply don't know what setting I need to pass.
Exact kernel message: "Jumbo frames cannot be enabled when both receive checksum offload and receive hashing are enabled. Disable one of the receive offload features before enabling jumbos."
Quoted 8 lines · D. Stussy
There has been some changes to the driver such that things like checksum verification is offloaded from the CPU. However, this blocks the ability to set a jumbo frame. The kernel does record an error indicating that checksum offloading need be disabled fro jumbo frame MTU sizes to be used. My e1000 interfaces use the 82574L chipset.
1) Was this an intentional change?
Yes, but I understand Intel is trying to come up with a way not to need it.
Quoted 3 lines
2) How do I disable that function so I can set jumbo frames with "ifconfig" or "ip"? I simply don't know what setting I need to pass.
ethtool can do it. Check its manpage, it can manipulate the various NIC offload engines, as well as other parameters such as dma ring buffer size, etc.
Signature · 4 lines
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