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Usage
Information
The order option is relevant in the context of the Policy QoS feature only. For more information, refer to
the Quality of Service chapter of the Dell Networking OS Configuration Guide.
You can configure either count (packets) or count (bytes). However, for an ACL with multiple rules, you
can configure some ACLs with count (packets) and others as count (bytes) at any given time.
When the configured maximum threshold is exceeded, generation of logs is stopped. When the interval
at which ACL logs are configured to be recorded expires, the subsequent, fresh interval timer is started
and the packet count for that new interval commences from zero. If ACL logging was stopped previously
because the configured threshold is exceeded, it is re-enabled for this new interval.
If ACL logging is stopped because the configured threshold is exceeded, it is re-enabled after the logging
interval period elapses. ACL logging is supported for standard and extended IPv4 ACLs, IPv6 ACLs, and
s MAC ACLs. You can configure ACL logging only on ACLs that are applied to ingress interfaces; you
cannot enable logging for ACLs that are associated with egress interfaces.
You can activate flow-based monitoring for a monitoring session by entering the flow-based enable
command in the Monitor Session mode. When you enable this capability, traffic with particular flows
that are traversing through the ingress and egress interfaces are examined and appropriate ACLs can
be applied in both the ingress and egress direction. Flow-based monitoring conserves bandwidth by
monitoring only the specified traffic instead of all traffic on the interface. This feature is particularly
useful when looking for malicious traffic. It is available for Layer 2 and Layer 3 ingress and egress traffic.
You may specify traffic using standard or extended access-lists. This mechanism copies all incoming
or outgoing packets on one port and forwards (mirrors) them to another port. The source port is the
monitored port (MD) and the destination port is the monitoring port (MG).
Related
Commands
ip access-list standard— configures a standard ACL.
permit — configures a MAC address filter to pass packets.
seq — configures a MAC address filter with a specified sequence number.
seq
Assign a sequence number to a deny or permit filter in an extended IP access list while creating the filter.
Syntax
seq sequence-number {deny | permit} {source [mask] | any | host ip-
address}} [count [byte] [dscp value] [order] [fragments] [threshold-in-msgs
[count]
Parameters
sequence-
number
Enter a number from 0 to 4294967290. The range is from 0 to 65534.
deny Enter the keyword deny to configure a filter to drop packets meeting this
condition.
permit Enter the keyword permit to configure a filter to forward packets meeting this
criteria.
source Enter an IP address in dotted decimal format of the network from which the packet
was received.
mask (OPTIONAL) Enter a network mask in /prefix format (/x) or A.B.C.D. The mask,
when specified in A.B.C.D format, may be either contiguous or non-contiguous.
any Enter the keyword any to specify that all routes are subject to the filter.
count (OPTIONAL) Enter the keyword count to count packets the filter processes.
byte (OPTIONAL) Enter the keyword byte to count bytes the filter processes.
dscp (OPTIONAL) Enter the keyword dcsp to match to the IP DCSCP values.
order (OPTIONAL) Enter the keyword order to specify the QoS order for the ACL
entry. The range is from 0 to 254 (where 0 is the highest priority and 254 is the
lowest; lower-order numbers have a higher priority). If you do not use the keyword
order, the ACLs have the lowest order by default (255).
Access Control Lists (ACL) 193