Dell PowerConnect 6224 Command Line Interface Manual page 1231

Max Header Size
Example
console# #show sflow 1 sampling
Sampler
Data Source
-----------
1/g1
The maximum number of bytes that should be copied from a
sampled packet to form a flow sample.
Receiver Packet
Index Sampling Rate
------- -------------
1 0
Max Header
Size
----------
128
Sflow Commands
1231