Q60Infrastructure Security
Refer to the exhibit. An engineer configures uRPF to improve security and prevent incoming spoofed IP packets. After the configuration, the same asymmetrically routed packets are also blocked. Which command resolves the issue?
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3
C: ip verify unicast reverse-path is the command for older IOS versions, and it only supports strict mode
D: This command does not exist. reverse-path does not support loose mode.
B: This is what is currently configured.
A: We want to allow asymmetrically returning traffic by using loose mode.
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C. This is the standard reachable-via rx command for older ios versions
D: This command doesn't exist. Older IOS versions didn't support asymmetrical URPF
B: This is the issue we are trying to solve
Answer = A
A 1
Selected Answer: A
A is correct. You need to use the loose RPF commands
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key word is assymettric: Which means it's coming back on an interface that was not intended (not the next hop). Setting it to any means source can be any interface (not next hop)
A 1
Selected Answer: A
Assymetric traffic = loose mode = ip verify unicast source ...any