When you use the log option, the CP processor logs details the packets that
match. Depending on how many packets match the log entry and at what rate, the
CP may become busy as it has to log these packets’ details.
deny tcp
Configure a filter that drops transmission control protocol (TCP) packets meeting the filter criteria.
Syntax
deny tcp {source mask | any | host ip-address} [bit] [operator
port [port]] {destination mask | any | host ip-address} [dscp]
[
bit] [operator port [port]] [count [byte] [order] [fragments]
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 deny 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 are 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.
dscp Enter this keyword dscp to deny a packet based on the
DSCP value. The range is from 0 to 63.
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
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)
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Access Control Lists (ACL)
