Configuring The Maximum Number Of Equal Cost Routes; Configuring Is-Is Route Summarization - H3C S7500E Series Operation Manual

Operation Manual – IPv4 Routing
H3C S7500E Series Ethernet Switches
Enable automatic IS-IS
cost calculation
Note:
In the case no interface cost is specified in interface view or system view and automatic
cost calculation is enabled:
When the cost style is wide or wide-compatible, IS-IS automatically calculates the
interface cost based on the interface bandwidth, using the formula: interface cost =
bandwidth reference value/interface bandwidth, and the maximum calculated cost is
16777214.
When the cost style is narrow, narrow-compatible, or compatible, if the interface
is a loopback interface, the cost value is 0; otherwise, the cost value is automatically
calculated as follows: if the interface bandwidth is in the range of 1 M to 10 M, the
interface cost is 60; if the interface bandwidth is in the range of 11 M to 100 M, the
interface cost is 50; if the interface bandwidth is in the range of 101 M to 155 M, the
interface cost is 40; if the interface bandwidth is in the range of 156 M to 622 M, the
interface cost is 30; if the interface bandwidth is in the range of 623 M to 2500 M, the
interface cost is 20, and the default interface cost of 10 is used for any other
bandwidths.

4.4.4 Configuring the Maximum Number of Equal Cost Routes

If there are more than one equal cost routes to the same destination, the traffic can be
load balanced to enhance efficiency.
Follow these steps to configure the maximum number of equal cost routes:
Enter system view
Enter IS-IS view
Specify the maximum
number of equal cost
routes for load balancing

4.4.5 Configuring IS-IS Route Summarization

This task is to configure a summary route, so routes falling into the network range of the
summary route are summarized with one route for advertisement. Doing so can reduce
To do...
auto-cost enable
To do...
system-view
isis [ process-id ]
maximum
load-balancing number
Use the command...
Use the command...
4-22
Chapter 4 IS-IS Configuration
Remarks
Required
Disabled by default.
Remarks
––
––
Optional
The default number is 4.