Dell S6100, Руководство по настройке

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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).
deny tcp (for IPv6 ACLs)
Configure a filter that drops TCP packets that match the filter criteria.
Syntax deny tcp { source address mask | any | host ipv6-address } [ operator port [ port ]]
{ destination address | any | host ipv6-address } [ bit ] [ operator port [ port ]]
[count [byte]] [log [interval minutes ] [threshold-in-msgs [ count ]] [monitor]
To remove this filter, you have two choices:
• Use the
no seq sequence-number
command syntax if you know the filter’s sequence number
• Use the
no deny tcp { source address mask | any | host ipv6-address }
{ destination address | any | host ipv6-address }
command
Parameters
source address
mask Enter a network mask in /prefix format (/x).
any Enter the keyword
any
to specify that all routes are subject to the filter.
host ipv6-address Enter the keyword
host
then the IP address to specify a host IP address.
destination address Enter the IPv6 address of the network or host to which the packets are sent.
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
•
established:
datagram of established TCP session
Use the
established
flag to match only ACK and RST flags of established TCP
session.
You cannot use
established
along with the other control flags
While using the established flag in an ACL rule, all the other TCP control flags are
masked, to avoid redundant TCP control flags configuration in a single rule. When you use
Access Control Lists (ACL) 327