Administrator Guide
deny udp
To drop user datagram protocol (UDP) packets meeting the filter criteria, configure a filter.
Syntax
deny udp {source mask | any | host ip-address} [operator port [port]]
{destination mask | any | host ip-address} [ttl operator] [dscp] [operator
port [port]] [count [byte] [order] [fragments] [monitor] [no-drop]
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 udp {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.
ttl Enter the keyword ttl to deny a packet based on the time to live value. The range
is from 1 to 255.
operator
Enter one of the following logical operand:
● eq(equal to) — matches packets that contain a ttl value that is equal to the
specified ttl value.
● neq(not equal to) — matches packets that contain a ttl value that is not equal
to the specified ttl value.
● gt(greater than) — matches packets that contain a ttl value that is greater
than the specified ttl value.
● lt (less than) — matches packets that contain a ttl value that is less than the
specified ttl value.
● range(inclusive range of values) — matches packets that contain a ttl value
that falls between the specified range of ttl values.
dscp Enter this 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
command)
port port
Enter the application layer port number. Enter two port numbers if using the range
logical operand. The range is from 0 to 65535.
destination
Enter the IP address of the network or host to 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.
count (OPTIONAL) Enter the keyword count to count packets processed by the filter.
byte (OPTIONAL) Enter the keyword byte to count bytes processed by the filter.
order (OPTIONAL) Enter the keyword order to specify the QoS priority for the ACL
entry. The range is from 0 to 254 (where 0 is the highest priority and 254 is the
lowest; lower-order numbers have a higher priority) If you did not use the keyword
order, the ACLs have the lowest order by default (255).
208 Access Control Lists (ACL)