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CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} tcp {source mask | any | host ip-
address}} [count [byte]] [order] [fragments]
Example of the seq Command
When you create the filters with a specific sequence number, you can create the filters in any order and
the filters are placed in the correct order.
NOTE: When assigning sequence numbers to filters, you may have to insert a new filter. To prevent
reconfiguring multiple filters, assign sequence numbers in multiples of five or another number.
The example below shows how the seq command orders the filters according to the sequence number
assigned. In the example, filter 15 was configured before filter 5, but the show config command
displays the filters in the correct order.
Dell(config-ext-nacl)#seq 15 deny ip host 112.45.0.0 any log
Dell(config-ext-nacl)#seq 5 permit tcp 12.1.3.45 0.0.255.255 any
Dell(config-ext-nacl)#show confi
!
ip access-list extended dilling
seq 5 permit tcp 12.1.0.0 0.0.255.255 any
seq 15 deny ip host 112.45.0.0 any log
Dell(config-ext-nacl)#
Configuring Filters Without a Sequence Number
If you are creating an extended ACL with only one or two filters, you can let the system assign a
sequence number based on the order in which the filters are configured. Filters are assigned in multiples
of five.
To configure a filter for an extended IP ACL without a specified sequence number, use any or all of the
following commands:
• Configure a deny or permit filter to examine IP packets.
CONFIG-EXT-NACL mode
{deny | permit} {source mask | any | host ip-address} [count [byte]] [order]
[fragments]
• Configure a deny or permit filter to examine TCP packets.
CONFIG-EXT-NACL mode
{deny | permit} tcp {source mask] | any | host ip-address}} [count [byte]]
[order] [fragments]
• Configure a deny or permit filter to examine UDP packets.
CONFIG-EXT-NACL mode
{deny | permit} udp {source mask | any | host ip-address}} [count [byte]]
[order] [fragments]
When you use the log keyword, the CP logs details about the packets that match. Depending on how
many packets match the log entry and at what rate, the CP may become busy as it has to log these
packets’ details.
The following example shows an extended IP ACL in which the sequence numbers were assigned by the
software. The filters were assigned sequence numbers based on the order in which they were configured
Access Control Lists (ACLs)
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