A Cisco router is configured to run OSPFv2 without an explicitly configured manual router … — Cisco CCNA

A Cisco router is configured to run OSPFv2 without an explicitly configured manual router ID. The router has the following active interface IP addresses:

- Loopback0: $10.10.1.1/32$
- Loopback1: $10.20.1.1/32$
- GigabitEthernet0/0: $192.168.1.254/24$
- GigabitEthernet0/1: $172.16.50.1/24$

Which IP address will OSPFv2 select as the router ID?

$10.20.1.1$ Cevap
B
$192.168.1.254$
C
$10.10.1.1$
D
$172.16.50.1$

Cevap

The OSPFv2 router ID selected by the router is

10.20.1.1

In OSPFv2, when a router ID is not manually specified with the 'router-id' command, the router selects the highest IPv4 address among all active loopback interfaces. Comparing Loopback0 (

10.10.1.1

) and Loopback1 (

10.20.1.1

10.20.1.1

is the highest loopback IP address and is selected as the OSPF Router ID.

Adım Adım Çözüm

Check for an explicitly configured manual OSPF Router ID

No manual 'router-id' command is present.

Manual configuration takes highest precedence in OSPF Router ID election.

Evaluate active loopback interfaces

Two active loopbacks exist: Loopback0 (

10.10.1.1

) and Loopback1 (

10.20.1.1

If no manual router ID is specified, OSPF evaluates active loopback interfaces next.

Select the highest IP address among active loopback interfaces

Compare

10.20.1.1

and

10.10.1.1

;

10.20.1.1

is numerically higher.

OSPF selects the highest active loopback IP address over lower loopbacks and over any physical interfaces.

Anahtar Kavram

OSPFv2 Router ID Election Precedence

Soru

Cevap

Adım Adım Çözüm

Anahtar Kavram

Sık Yapılan Hatalar

Konular

Bu konudan daha fazla soru