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Configuring a Standard IP ACL Filter
If you are creating a standard ACL with only one or two filters, you can let Dell EMC Networking OS assign a sequence number
based on the order in which the filters are configured. The software assigns filters in multiples of five.
1. Configure a standard IP ACL and assign it a unique name.
CONFIGURATION mode
ip access-list standard access-list-name
2. Configure a drop or forward IP ACL filter.
CONFIG-STD-NACL mode
{deny | permit} {source [mask] | any | host ip-address} [count [byte] [dscp] [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. The following example shows a
standard IP ACL in which Dell EMC Networking OS assigns the sequence numbers. The filters were assigned sequence numbers
based on the order in which they were configured (for example, the first filter was given the lowest sequence number). The
show config command in IP ACCESS LIST mode displays the two filters with the sequence numbers 5 and 10.
DellEMC(config-route-map)#ip access standard acl1
DellEMC(config-std-nacl)#permit 10.1.0.0/16 monitor 177
DellEMC(config-std-nacl)#show config
!
ip access-list standard acl1
seq 5 permit 10.1.0.0/16 monitor 177
DellEMC(config-std-nacl)#
To view all configured IP ACLs, use the show ip accounting access-list command in EXEC Privilege mode.
The following examples shows how to view a standard ACL filter sequence for an interface.
DellEMC#show ip accounting access example interface gig 4/12
Extended IP access list example
seq 15 deny udp any any eq 111
seq 20 deny udp any any eq 2049
seq 25 deny udp any any eq 31337
seq 30 deny tcp any any range 12345 12346
seq 35 permit udp host 10.21.126.225 10.4.5.0 /28 monitor 300
seq 40 permit udp host 10.21.126.226 10.4.5.0 /28
seq 45 permit udp 10.8.0.0 /16 10.50.188.118 /31 range 1812 1813
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.
The traffic passes through the filter in the order of the filter’s sequence and hence 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.
Access Control Lists (ACLs)
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