Dell S6100, Руководство по настройке

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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
•
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
any TCP control flag in an ACL rule,
established
is masked and other control flags are
available.
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
•
range
= inclusive range of ports (you must specify two ports for the port parameter)
port port Enter the application layer port number. Enter two port numbers if you are using the
range logical operand. The range is from 0 to 65535.
The following list includes some common TCP port numbers:
• 23 = Telnet
• 20 and 21 = FTP
• 25 = SMTP
214 Access Control Lists (ACL)