3com 4500 26-PORT User Manual

Page of 466
IP Routing Policy Configuration Commands
171
index_number
 Identify an item in the prefix address list. The item with smaller 
index-number will be tested first. 
permit
 Enter to specify the match mode of the defined address prefix list items as 
permit mode. 
deny
 Enter to specify the match mode of the defined address prefix list items as 
deny mode. 
network
 Enter the IP address prefix range (IP address). If it is 0.0.0.0 0, all the IP 
addresses are matched.
len
 Enter the IP address prefix range (mask length). If it is 0.0.0.0 0, all the IP 
addresses are matched.
greater_equalless_equal
 The address prefix range [greater-equal, less-equal] 
to be matched after the address prefix network len has been matched. The 
meaning of 
greater
-equal
 is "larger than or equal to" , and the meaning of 
less-equal
 is "less than or equal to". The range is len <= greater-equal <= 
less-equal <= 32. When only 
greater-equal
 is used, it denotes the prefix range 
[greater-equal, 32]. When only 
less-equal
 is used, it denotes the prefix range 
[len, less-equal].
Description
Use the 
ip ip-prefix
 command to configure an address prefix list or one of its 
items. 
Use the 
undo ip ip-prefix
 command to delete an address prefix list or one of its 
items.
By default, there’s no address prefix list.
The address prefix list is used for IP address filtering. An address prefix list may 
contain several items, and each item specifies one address prefix range. The 
inter-item filtering relation is "OR", i.e. passing an item means passing the filtering 
of this address prefix list. Not passing the filtering of any item means not passing 
the filtration of this prefix address list.
The address prefix range may contain two parts, which are determined by 
len
 and 
[
greater-equal, less-equal
] respectively. If the prefix ranges of these two parts 
are both specified, the IP to be filtered must match the prefix ranges of these two 
parts.
If you specify 
network len
 as 0.0.0.0 0, it only matches the default route.
Example
The prefix address list of this address indicates to match the bits 1 to 8 and the bits 
17 to 18 for filtering the IP address with the bits 1 to 8 and the bits 17 to 18 of the 
specified IP network segment 10.0.192.0. 
<4500>system-view
System View: return to User View with Ctrl+Z.
[4500]ip ip-prefix p1 permit 10.0.192.0 8 greater-equal 17 
less-equal 18