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port (Security Source NAT)


Hierarchy Level


Specify the Port Address Translation (PAT) for a source pool.


  • block-allocation—Allocates a block of ports for translation, instead of allocating individual ports.

  • deterministic—Maps an incoming (source) IP address and port to the specific destination address and port block, based on a predefined deterministic NAT algorithm.

  • no-translation—Specifies that no PAT is required. This option cannot be configured with the port-overloading-factor or range options.

  • port-overloading-factor number—Configures the port overloading capacity in source NAT. This option cannot be configured with the no-translation option.

  • range port-low <to port-high>—Specifies the port number range attached to each address in the pool. This option cannot be configured with the no-translation option.

  • twin port—Configures the twin port range for source NAT pools to avoid port overloading.

The remaining statements are explained separately.

Required Privilege Level

security—To view this statement in the configuration.

security-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 9.2. Statement updated with block-allocation, deterministic, and twin-port options in Junos OS Release 12.1X47-D10. Statement updated with interim-logging-interval and last-block-recycle-timeout options in Junos OS Release 15.1X49-D60.