A four-member port channel can be healthy while one transfer uses only one member. Before replacing optics or increasing buffers, separate aggregate capacity from the forwarding decision for an individual flow. Linux bonding documentation explicitly notes that its layer3+4 policy can distribute traffic to one peer across members, but a single connection does not span multiple members.[1]
This guide is a practical diagnostic workflow for conventional Ethernet LACP and Linux 802.3ad bonds—not a claim about RDMA multipathing or GPU fabric performance. The design and test cases below are hypothetical; no production benchmark or failover test was run for this article.
