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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.
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
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 specified traffic instead 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).
permit tcp
To pass TCP packets meeting the filter criteria, configure a filter.
Syntax
permit tcp {source mask | any | host ip-address} [bit] [operator port
[port]] {destination mask | any | host ip-address} [bit] [dscp] [operator
port [port]] [count [byte]] [order] [fragments][log [interval minutes]
[threshold-in-msgs [count]] [monitor]
To remove this filter, you have two choices:
● Use the no seq sequence-number command if you know the filter’s sequence number.
● Use the no permit tcp {source mask | any | host ip-address} {destination
mask | any | host ip-address} command.
Parameters
source Enter the IP address of the network or host from which the packets were sent.
mask 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.
host ip-address Enter the keyword host then the IP address to specify a host IP address.
bit Enter a flag or combination of bits:
● ack: acknowledgement field
● fin: finish (no more data from the user)
● psh: push function
● rst: reset the connection
● syn: synchronize sequence numbers
● urg: urgent field
dscp Enter the keyword dscp to deny a packet based on the DSCP value. The range is
from 0 to 63.
operator (OPTIONAL) Enter one of the following logical operand:
● eq = equal to
● neq = not equal to
● gt = greater than
● lt = less than
Access Control Lists (ACL) 161