Cisco 4500M Software Manual page 100

Configuring ICMP
To have the Cisco IOS software respond to ICMP mask requests by sending ICMP Mask Reply
messages, perform this task:
Command
Switch (config-if)# [no] ip mask-reply
Software Configuration Guide—Release 12.2(25)EW
5-12
Chapter 5 Checking Port Status and Connectivity
Purpose
Enables response to ICMP destination mask requests.
Use the no keyword to disable this functionality.
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