Dell Force10 MXL Blade Configuration Manual page 89

If you want to forward all routes that do not match the prefix list criteria, you must configure a prefix list
filter to permit all routes (
list. To permit the default route only, enter
Figure 5-15 shows how the
the example, filter 20 was configured before filter 15 and 12, but the
filters in the correct order.
Figure 5-15. Command Example: seq
FTOS(conf-nprefixl)#seq 20 permit 0.0.0.0/0 le 32
FTOS(conf-nprefixl)#seq 12 deny 134.23.0.0 /16
FTOS(conf-nprefixl)#seq 15 deny 120.23.14.0 /8 le 16
FTOS(conf-nprefixl)#show config
!
ip prefix-list juba
seq 12 deny 134.23.0.0/16
seq 15 deny 120.0.0.0/8 le 16
seq 20 permit 0.0.0.0/0 le 32
FTOS(conf-nprefixl)#
Note the last line in the prefix list "juba" contains a "permit all" statement. By including this line in a
prefix list, you specify that all routes not matching any criteria in the prefix list are forwarded.
To delete a filter, use the
If you are creating a standard prefix list with only one or two filters, you can let FTOS assign a sequence
number based on the order in which the filters are configured. FTOS assigns filters in multiples of five.
To configure a filter without a specified sequence number, follow these steps, starting in
CONFIGURATION mode:
Step Command Syntax
1 ip prefix-list prefix-name
2
{deny | permit} ip-prefix [ge
min-prefix-length] le
max-prefix-length]
). The "permit all" filter must be the last filter in your prefix
permit 0.0.0.0/0 le 32
permit 0.0.0.0/0
command orders the filters according to the sequence number assigned. In
seq
no seq sequence-number
Command Mode
CONFIGURATION
CONFIG-NPREFIXL
.
show config
command in PREFIX LIST mode.
Purpose
Create a prefix list and assign it a unique
name.
Create a prefix list filter with a deny or
permit action. The optional parameters are:
•
ge min-prefix-length:
prefix length to be matched (0 to 32).
•
le max-prefix-length:
prefix length to be matched (0 to 32).
command displays the
is the minimum
is the maximum
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