If multiple equal-cost IS-IS routes are available on a network, configure the equal-cost IS-IS routes to work in load-balancing mode to increase the bandwidth usage of each link.
If there are redundant IPv6 IS-IS links, multiple routes may have an equal cost. Configure the equal-cost IPv6 IS-IS routes to work in load-balancing mode so that traffic will be evenly balanced among these links.
This mechanism increases the link bandwidth usage and prevents network congestion caused by link overload. However, this mechanism may make traffic management more difficult because traffic will be randomly forwarded.
isis [ process-id ]
ipv6 maximum load-balancing number