Ospf Network Adjustment And Optimization; Configuring Ospf Timers - H3C S7500 Series Operation Manual

Operation Manual – Routing Protocol
H3C S7500 Series Ethernet Switches
Note:
The import-route command cannot import the default route. To import the default
route, you must use the default-route-advertise command.
The filtering of advertised routes by OSPF means that OSPF only converts the
external routes meeting the filter criteria into Type-5 or Type-7 LSAs and
advertises them.
When enabling OSPF to redistribute routes, you can also configure the defaults of
some additional parameters, such as cost, number of routes, tag, and type. A route
tag can be used to identify protocol-related information.
Use the keyword allow-ibgp with care when redistributing routes from BGP,
because it redistributes IBGP routes without keeping the AS_PATH attribute,
which may lead to routing loops between ASs.

4.7 OSPF Network Adjustment and Optimization

You can adjust and optimize an OSPF network in the following aspects:
By changing the OSPF packet timers, you can adjust the convergence speed of
the OSPF network and the network load brought by OSPF packets. On some
low-speed links, you need to consider the delay experienced when the interfaces
transmit LSAs.
By adjusting SPF calculation interval, you can mitigate resource consumption
caused by frequent network changes.
In a network with high security requirements, you can enable OSPF
authentication to enhance OSPF network security.
In addition, OSPF supports network management. You can configure the binding
of the OSPF MIB with an OSPF process and configure the Trap message
transmission and logging functions.
4.7.1 Configuration Prerequisites
Before adjusting and optimizing an OSPF network, perform the following tasks:
Configuring the network layer addresses of interfaces so that the adjacent nodes
are reachable to each other at the network layer
Configuring basic OSPF functions

4.7.2 Configuring OSPF Timers

The Hello intervals for OSPF neighbors must be consistent. The value of Hello
interval is in inverse proportion to route convergence speed and network load.
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Chapter 4 OSPF Configuration