Use LAGs for Bandwidth and Redundancy
A Link Aggregation Group (LAG) combines multiple physical links into one logical connection. It can increase total bandwidth while allowing traffic to continue when a member link fails.
What two 10 Gbit/s links provide
A two-member LAG offers up to 20 Gbit/s of total aggregated bandwidth. If one member fails, the remaining link can carry up to 10 Gbit/s.
One flow is still one flow
Traffic can be distributed across LAG members, but one connection or traffic flow is normally still limited to the speed of one physical member link.
Configure both sides
Assign the relevant ports to the same LAG on both connected devices. Simply inserting multiple cables does not create an aggregated connection.
Use links with matching speeds, verify that every intended member is active, and keep enough surviving capacity for required traffic after one member fails.