Dell Command Line Reference Guide for the S4048–ON System 9.14.2.8

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permit udp

To pass UDP packets meeting the filter criteria, configure a filter.

Syntax
permit 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 permit 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 and then enter the IP address to specify a host IP address.
ttl
Enter the keyword ttl to permit 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 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 0 to 65535.
destination
Enter the IP address of the network or host to which the packets are sent.
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 do not use the keyword order, the ACLs have the lowest order by default (255).
fragments
Enter the keyword fragments to use ACLs to control packet fragments.
monitor
(OPTIONAL) Enter the keyword monitor to describe the traffic that you want to monitor and the ACL in which you are creating the rule is applied to the monitored interface. For more information, see “Flow-based Monitoring” in the Port Monitoring section of the Dell EMC Networking OS Configuration Guide.
no-drop
Enter the keywords no-drop to match only the forwarded packets.
Defaults
Not configured.
Command Modes
CONFIGURATION-EXTENDED-ACCESS-LIST
Command History

This guide is platform-specific. For command information about other platforms, see the relevant Dell EMC Networking OS Command Line Reference Guide.

Version
Description
9.12(0.0)
Introduced the ttl parameter. Removed the session–ID option from the monitor parameter.
9.11(0.0)
Added support for session–ID to the monitor parameter.
9.10(0.1)
Introduced on the S6010-ON and S4048T-ON.
9.10(0.0)
Introduced on the S3148.
9.10(0.0)
Introduced on the S6100-ON.
9.8(2.0)
Introduced on the S3100 series.
9.8(1.0)
Introduced on the Z9100–ON.
9.8(0.0P5)
Introduced on the S4048-ON.
9.8(0.0P2)
Introduced on the S3048-ON.
9.8(0.0)
Added the no-drop parameter.
9.7(0.0)
Introduced on the S6000–ON.
9.2(1.0)
Introduced on the Z9500.
8.3.19.0
Introduced on the S4820T.
8.3.11.1
Introduced on the Z9000.
8.3.7.0
Introduced on the S4810.
8.3.1.0
Added the keyword dscp.
8.2.1.0
Allows ACL control of fragmented packets for IP (Layer 3) ACLs.
8.1.1.0
Introduced on the E-Series.
7.6.1.0
Introduced on the S-Series.
7.5.1.0
Introduced on the C-Series.
7.4.1.0
Added support for non-contiguous mask and added the monitor option. .
6.5.10
Expanded to include the optional QoS order priority for the ACL entry.
Usage Information

The order option is relevant in the context of the Policy QoS feature only. For more information, see the “Quality of Service” section of the Dell EMC Networking OS Configuration Guide.

NOTE: When you configure ACL logging and byte counters simultaneously, byte counters may display an incorrect value. Configure packet counters with logging instead.

The S-Series cannot count both packets and bytes; when you enter the count byte options, only bytes increment.

The monitor option is relevant in the context of flow-based monitoring only. For more information, refer to Port Monitoring.

Most ACL rules require one entry in the CAM. However, rules with TCP and UDP port operators (for example, gt, lt, or range) may require more than one entry. The range of ports is configured in the CAM based on bit mask boundaries; the space required depends on exactly what ports are included in the range.

Example

An ACL rule with a TCP port range of 4000–8000 uses eight entries in the CAM.

DellEMC# Data             Mask         From To   #Covered

1 0000111110100000 1111111111100000 4000 4031 32
2 0000111111000000 1111111111000000 4032 4095 64
3 0001000000000000 1111100000000000 4096 6143 2048
4 0001100000000000 1111110000000000 6144 7167 1024
5 0001110000000000 1111111000000000 7168 7679 512
6 0001111000000000 1111111100000000 7680 7935 256
7 0001111100000000 1111111111000000 7936 7999 64
8 0001111101000000 1111111111111111 8000 8000 1

Total Ports: 4001
Example

An ACL rule with a TCP port lt 1023 uses only one entry in the CAM.

DellEMC# Data            Mask          From To   #Covered

1 0000000000000000 1111110000000000 0    1023 1024

Total Ports: 1024
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