Reference Guide

When you use the log option, the CP processor logs details about 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.
The monitor option is relevant in the context of flow-based monitoring only. For more
information, refer to
Port Monitoring.
NOTE: When ACL logging and byte counters are configured simultaneously, byte counters
may display an incorrect value. Configure packet counters with logging instead.
permit tcp
Configure a filter to pass TCP packets meeting the filter criteria.
C-Series, E-Series, S-Series, Z-Series
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] |
log] [order] [monitor] [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 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 and then enter 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 0 to 63.
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