3Com Switch 8807, Configuration Manual

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OSPF GR Overview 307
Figure 73 Area and route summary
OSPF Features
Supported by Switch
8800 Family Series
The Switch 8800 Family series support the following OSPF features:
■
Support stub areas: OSPF defines stub areas to decrease the overhead when
the routers within the area receive ASE routes.
■
Support NSSA: OSPF defines NSSA areas, surmounting the restriction of stub
areas on topology. NSSA is the abbreviation of Not-So-Stubby Area.
■
Support OSPF Multi-Process: A router runs multiple OSPF processes.
■
Share the discovered routing information with other dynamic routing
protocols: OSPF currently can import static routes and routes of other dynamic
routing protocols such as RIP into the autonomous system of the router, or
advertise the routing information discovered by OSPF to other routing
protocols.
■
Authenticator: OSPF provides clear text authenticator and MD5 encryption
authenticator to authenticate packets transmitted between neighboring
routers in the same area.
■
Flexible configuration for the router port parameter: On the router port, you
can configure the following OSPF parameters: output cost, Hello packet
interval, retransmission interval, port transmission delay, route precedence,
invalid time for adjacent routers, packet authentication mode, packet
authenticator, and others.
■
Virtual connection: Creates and configures virtual connections.
■
Abundant debugging information: OSPF provides abundant debugging
information, consequently helping users to diagnose failure
OSPF GR Overview
Open Shortest Path First (OSPF) is an internal gateway protocol. It is developed by
IETF based on link state algorithm. OSPF version 2 (RFC2328) is now commonly
used.
Graceful Restart (GR) is designed to keep the OSPF routing data normal when
abnormal switchover occurs on the switch, so that critical services will not be
interrupted.
Area 12
Area 8
Area 19
Area 0
Virtual Link
19.1.1.0/24
19.1.2.0/24
19.1.3.0/24
RTA