✨ Bandwidth validation

[TylerGillson]

Summary

• Call iperf3 to benchmark network bandwidth between localhost and iperf server over a given duration.
• Parse the output to determine the minimum bandwidth.
• Fail if the minimum falls below the target threshold.

Design

• The network plugin controller could optionally start an iperf server process
• Bandwidth validation would be supported between two validator installations (both acting as either client or server)
• Requires ingress config for the network plugin, OR user-provided host name of a separate iperf server