3com MSR 20-20 참조 매뉴얼

Use the undo ip ip-prefix command to remove an IPv4 prefix list or an item.

No IPv4 prefix list is configured by default.

An IPv4 prefix list is used to filter IPv4 addresses. It may have multiple items, each 
of which specifies a range of IPv4 prefix. The filtering relation among items is logic 
OR, namely, passing any item means the IPv4 prefix list is passed. If no item is 
passed, the IP prefix list cannot be passed.

The IP prefix range is determined by mask-length and [ min-mask-length, 
max-mask-length ]. If both mask-length and [ min-mask-length, 
max-mask-length ] are specified, then the IP address to be filtered must satisfy 
both of them.

If ip-address mask-length is specified as 0.0.0.0 0, then only the default routes will 
be matched.

To match all the routes, use 0.0.0.0 0 less-equal 32.

# Create a routing policy named policy1 with node 10, matching mode as permit. 
Define an IP prefix list named p1 to permit only the routes in the network segment 
10.0.192.0/8 and with mask length 17 or 18.

<Sysname> system-view

[Sysname] ip ip-prefix p1 permit 10.0.192.0 8 greater-equal 17 less-equal 18 

reset ip ip-prefix [ ip-prefix-name ]

User view

ip-prefix-name: IP prefix list name, a string of 1 to 19 characters.

Use the reset ip ip-prefix command to clear the statistics of a specified IPv4 
prefix list. If no ip-prefix-name is specified, the statistics of all the IPv4 prefix lists 
will be cleared.

# Clear the statistics of IPv4 prefix list abc.

<Sysname> reset ip ip-prefix abc