HP (Hewlett-Packard) 6208M-SX Switch User Manual


 
Network Address Translation
Enabling NAT
The NAT configuration does not take effect until you enable it on specific interfaces. You can enable NAT on
Ethernet ports and on virtual interfaces. You also can enable the feature on the primary port of a trunk group, in
which case the feature applies to all the ports in the trunk group.
NOTE: You must configure inside NAT on one interface and outside NAT on another interface. The device
performs NAT for traffic between the interfaces.
To enable NAT, use the following CLI methods.
Enabling Inside NAT
To enable inside NAT on the interface attached to the private addresses, use the following CLI method.
USING THE CLI
To enable inside NAT on an interface, enter commands such as the following:
HP9300(config)# interface ethernet 1/1
HP9300(config-if-1/1)# ip nat inside
This command enables inside NAT on Ethernet port 1/1.
Syntax: [no] ip nat inside
To enable inside NAT on a virtual interface, enter commands such as the following:
HP9300(config)# interface ve 1
HP9300(config-vif-1)# ip nat inside
This command enables inside NAT on virtual interface 4.
Enabling Outside NAT
To enable outside NAT on the interface attached to public addresses, use the following CLI method.
USING THE CLI
To enable outside NAT on an interface, enter commands such as the following:
HP9300(config)# interface ethernet 1/2
HP9300(config-if-1/2)# ip nat outside
This command enables outside NAT on Ethernet port 1/2.
Syntax: [no] ip nat outside
To enable outside NAT on a virtual interface, enter commands such as the following:
HP9300(config)# interface ve 2
HP9300(config-vif-2)# ip nat outside
This command enables outside NAT on virtual interface 4.
Changing Translation Table Timeouts
The NAT translation table contains all the currently active NAT translation entries on the device. An active entry is
one that the device created for a private address when that client at that address sent traffic to the Internet. NAT
performs the following steps to provide an address translation for a source IP address:
The feature looks in the NAT translation table for an active NAT entry for the translation. If the table contains
an active entry for the session, the device uses that entry.
If NAT does not find an active entry in the NAT translation table, NAT creates an entry and places the entry in
the table. The entry remains in the table until the entry times out.
Each NAT entry remains in the NAT translation table until the entry ages out. The age timers apply globally to all
interfaces on which NAT is enabled.
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