Reference Guide

IPv6 Access Control Lists (IPv6 ACLs) | 689
deny tcp
c e s
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] [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
or
• Use the no deny tcp {source address mask | any | host ipv6-address} {destination
address | any | host ipv6-address} command.
Parameters
source address
Enter the IPv6 address of the network or host from which the packets were sent
in the
x:x:x:x::x format followed by the prefix length in the /x format.
Range: /0 to /128
The
:: notation specifies successive hexadecimal fields of zero.
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 followed by the IPv6 address of the host in the
x:x:x:x::x format.
The
:: notation specifies successive hexadecimal fields of zero
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
command parameter.
port port
Enter the application layer port number. Enter two port numbers if using the
range logical operand.
Range: 0 to 65535.
The following list includes some common TCP port numbers:
• 23 = Telnet
• 20 and 21 = FTP
• 25 = SMTP
• 169 = SNMP
destination address
Enter the IPv6 address of the network or host to which the packets are sent in
the
x:x:x:x::x format followed by the prefix length in the /x format.
Range: /0 to /128
The
:: notation specifies successive hexadecimal fields of zero.
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