A network engineer is configuring a backup path on router HQ-R1 to reach the corporate sub… — Cisco CCNA

A network engineer is configuring a backup path on router HQ-R1 to reach the corporate subnet $172.20.40.0/22$ . The primary route to this prefix is currently learned via Internal EIGRP with a default administrative distance of 90. The backup connection uses a point-to-point Ethernet link where HQ-R1 local interface GigabitEthernet0/1 is assigned IP address $198.51.100.1/30$ and the remote peer router interface is assigned $198.51.100.254/30$ .

Which Cisco IOS command must be configured on HQ-R1 to ensure the static route acts as a floating backup route that only enters the routing table if the primary EIGRP route fails?

ip route 172.20.40.0 255.255.252.0 198.51.100.254 95Cevap
B
ip route 172.20.40.0 255.255.252.0 198.51.100.254 85
C
ip route 172.20.40.0 0.0.3.255 198.51.100.254 95
D
ip route 172.20.40.0 255.255.252.0 198.51.100.1 95

Cevap

The correct command is `ip route 172.20.40.0 255.255.252.0 198.51.100.254 95`, which specifies the destination network, valid subnet mask, remote next-hop IP, and an administrative distance higher than Internal EIGRP (90).

The correct command properly formats the /22 mask as 255.255.252.0, uses the remote neighbor's interface IP (198.51.100.254) as the next hop, and sets an administrative distance of 95. Because 95 is higher than Internal EIGRP's administrative distance of 90, the router keeps this route out of the active routing table until the EIGRP route fails.

Adım Adım Çözüm

Convert the CIDR prefix length /22 to dotted-decimal subnet mask format.

A /22 prefix corresponds to 22 binary ones (11111111.11111111.11111100.00000000), which evaluates to 255.255.252.0.

Cisco IOS static routing syntax requires a valid IPv4 subnet mask following the destination network prefix.

Identify the correct next-hop IP address for static route forwarding.

The next-hop IP address must be the neighbor router's IP address on the point-to-point link, which is 198.51.100.254.

Configuring a local interface IP address as a next hop is invalid because a router cannot forward packets to its own local interface.

Determine the required Administrative Distance (AD) for a floating static route.

Select an administrative distance value strictly greater than 90 (e.g., 95).

Internal EIGRP has a default AD of 90. To act as a floating backup, the static route's AD must be higher than the active primary routing protocol so that it remains untrusted until the primary route drops from the routing table.

Anahtar Kavram

Floating Static Route Administrative Distance Configuration

Tahmini Süre:1m 30s

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Cevap

Adım Adım Çözüm

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