Link aggregation: two cables, one link

The idea

officeRouter and a file server are joined by two cables. Link aggregation makes them one link, agreed on by LACP at both ends: you will spread flows, not packets, over the two, and see one cable fail.

Steps

1. Two cables, one card

   The two cables are 100 Mbit/s each, and two parallel links would only let IP use one. List the cards whose master is officeRouter's bond0, then its address.

   officeRouter:~# ip -br link show master bond0
   officeRouter:~# ip -br addr show bond0

2. LACP: both ends agree

   A cable joins the bond only once both ends agree on it, by LACP messages sent every second on each cable, so a cable plugged in wrong never carries traffic. Show each member's LACP state.

   officeRouter:~# ip -d link show master bond0