R2511-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V5)

129
Interfaces with different network types operate differently. For example, broadcast interfaces on a
network must elect the DIS and flood CSNP packets to synchronize the LSDBs, but P2P interfaces on a
network do not need to elect the DIS, and have a different LSDB synchronization mechanism.
If only two routers exist on a broadcast network, configure the network type of attached interfaces as P2P
to avoid DIS election and CSNP flooding, saving network bandwidth and speeding up network
convergence.
To configure the network type of an interface:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Configure the network type for the
interface as P2P.
isis circuit-type p2p
Optional.
By default, the network type
of an interface depends on
the physical media.
Configuring IS-IS routing information control
Perform the tasks in this section to affect IS-IS route selection.
Configuration prerequisites
Before the configuration, complete the following tasks:
• Configure IP addresses for all interfaces, and make sure that all neighboring nodes are reachable
to each other at the network layer.
• Enable IS-IS.
Configuring IS-IS link cost
The IS-IS cost of an interface is determined in the following order:
1. IS-IS cost specified in interface view.
2. IS-IS cost specified in system view. The cost is applied to the interfaces associated with the IS-IS
process.
3. Automatically calculated cost. If the cost style is wide or wide-compatible, IS-IS automatically
calculates the cost using the formula: Interface cost = (Bandwidth reference value / Interface
bandwidth) ×10, which is in the range of 1 to 16777214. For other cost styles, Table 6 applies.
Table 6 Automatic cost calculation scheme for cost styles other than wide and wide-compatible
Interface bandwidth Interface cost
≤ 10 Mbps 60
≤ 100 Mbps 50
≤ 155 Mbps 40
≤ 622 Mbps 30