How configure multiple areas in OSPF?
How configure multiple areas in OSPF?
This time, we’ll take a look how you can configure multi area OSPF. Above we have R1 and R2 in area 0, the backbone area. Between R1 and R3, we will use area 1 and between R2/R4 we will use area 2. R3 and R4 have a loopback interface with an IP address that we will advertise in their area.
How is OSPF configured?
Configuring OSPF 1 Just like with other routing protocols covered so far (RIP, EIGRP) first you need to enable OSPF on a router. This is done by using the router ospf PROCESS-ID global configuration command. This is done by using the network IP_ADDRESS WILDCARD_MASK AREA_ID command from the ospf configuration mode.
Why we configure area in OSPF?
In OSPF, a single autonomous system (AS) can be divided into smaller groups called areas. This reduces the number of link-state advertisements (LSAs) and other OSPF overhead traffic sent on the network, and it reduces the size of the topology database that each router must maintain.
How many OSPF areas can be configured?
In general, to maximize stability, one router should not be in more than three areas. Designated router (DR) selection: In general, the DR and backup designated router (BDR) on a multiaccess link (for example, Ethernet) have the most OSPF work to do.
What is the main disadvantage of multi area OSPF?
Assuming proper OSPF design and configuration, using multiple area concept brings vanish these disadvantages: In multiple area concept updates are kept within an area. They are not extend to other areas. Therefore routers affected by change are only within an area.
What is the purpose of OSPF?
The OSPF (Open Shortest Path First) protocol is one of a family of IP Routing protocols, and is an Interior Gateway Protocol (IGP) for the Internet, used to distribute IP routing information throughout a single Autonomous System (AS) in an IP network.
What are two advantages of multi area OSPF?
Advantages of Multiarea OSPF: Smaller routing tables – Fewer routing table entries as network addresses can be summarized between areas. Reduced link-state update overhead. Reduced frequency of SPF calculations.
How does OSPF generate default routes?
In order for OSPF to generate a default route, you must use the default-information originate command. There are two ways to advertise a default route into a normal area. The first is to advertise 0.0.0.0 into the OSPF domain, provided the advertising router already has a default route.
What is the advantage of a “area” in OSPF configuration?
The advantages of an “area” in OSPF configuration are: smaller routing table (no summarization by default): fewer routing table entries as network addresses can be summarized between areas. smaller link-state database (LSDB): fewer routers exchanging LSAs, minimizes processing and memory requirements.
What is the use of process ID in OSPF?
It is used to create or modify an existing OSPF routing process and enters the user into OSPF router configuration mode. When configuring OSPF, process-id is used as an identifier of the local OSPF process; different OSPF process IDs would be used on the same router if multiple independent OSPF processes were being run on the same device.
What is the function of OSPF protocol?
The OSPF (Open Shortest Path First) protocol is one of a family of IP Routing protocols, and is an Interior Gateway Protocol (IGP) for the Internet, used to distribute IP routing information throughout a single Autonomous System (AS) in an IP network .