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seq 50 permit tcp 10.8.0.0 /16 10.50.188.118 /31 eq 49 monitor 349
seq 55 permit udp 10.15.1.0 /24 10.50.188.118 /31 range 1812 1813
To delete a filter, enter the show config command in IP ACCESS LIST mode and locate the sequence number of the filter you
want to delete. Then use the no seq sequence-number command in IP ACCESS LIST mode.
Configure an Extended IP ACL
Extended IP ACLs filter on source and destination IP addresses, IP host addresses, TCP addresses, TCP host addresses, UDP
addresses, and UDP host addresses.
Because traffic passes through the filter in the order of the filter’s sequence, you can configure the extended IP ACL by first
entering IP ACCESS LIST mode and then assigning a sequence number to the filter.
Configuring Filters with a Sequence Number
To configure filters with a sequence number, use the following commands.
1. Enter IP ACCESS LIST mode by creating an extended IP ACL.
CONFIGURATION mode
ip access-list extended access-list-name
2. Configure a drop or forward filter.
CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} {ip-protocol-number | icmp | ip | tcp | udp} {source
mask | any | host ip-address} {destination mask | any | host ip-address} [operator port
[port]] [count [byte] | log] [order] [monitor [session-id]] [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.
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, keep in mind that you might need to insert a new filter. To prevent
reconfiguring multiple filters, assign sequence numbers in multiples of five or another number.
The following example 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 monitor 209
Dell(config-ext-nacl)#show config
!
ip access-list extended dilling
seq 5 permit tcp 12.1.0.0 0.0.255.255 any monitor 209
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 Dell Networking OS assign a sequence number
based on the order in which the filters are configured. Dell Networking OS assigns filters 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] [monitor
[session-id]] [fragments]
● Configure a deny or permit filter to examine TCP packets.
CONFIG-EXT-NACL mode
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Access Control Lists (ACLs)