Understanding Source NAT Pools
For source NAT address pools, specify the following:
- Name of the source NAT address pool.
- Up to eight address or address ranges.
Note: Do not overlap NAT addresses for source NAT, destination NAT, and static NAT within one routing instance.
- Routing instance to which the pool belongs (the default is the main inet.0 routing instance).
- No port translation (optional)—By default, port address translation is performed with source NAT. If you specify the port no-translation option, the number of hosts that the source NAT pool can support is limited to the number of addresses in the pool.
- Overflow pool (optional)—Packets are dropped if there are no addresses available in the designated source NAT pool. To prevent that from happening when the port no-translation option is configured, you can specify an overflow pool. Once addresses from the original source NAT pool are exhausted, IP addresses and port numbers are allocated from the overflow pool. A user-defined source NAT pool or an egress interface can be used as the overflow pool. (When the overflow pool is used, the pool ID is returned with the address.)
- IP address shifting (optional)—A range of original source IP addresses can be mapped to another range of IP addresses by shifting the IP addresses. Specify the host-address-base option with the base address of the original source IP address range.
When the raise-threshold option is configured for source NAT, an SNMP trap is triggered if the source NAT pool utilization rises above this threshold. If the optional clear-threshold option is configured, an SNMP trap is triggered if the source NAT pool utilization drops below this threshold. If clear-threshold is not configured it is set by default to 80 percent of the raise-threshold value.
Related Topics
- JUNOS Software Feature Support Reference for SRX Series and J Series Devices
- Understanding Source NAT
- Source NAT Configuration Overview
- Understanding Source NAT Pools with PAT
- Understanding Source NAT Pools Without PAT
- Example: Configuring Source NAT Pools (CLI)
- Understanding Persistent Addresses