In static 1:1 NAT, inside IP addresses are statically mapped to the outside IP addresses. This way, devices on the outside can predictably initiate traffic to the devices on the inside.
Static configuration is based on the CLI concepts used in deterministic NAT. For example:
config
router
nat
inside
deterministic
prefix 10.0.0.0/24 subscriber-type classic-lsn-sub nat-policy ‛one-to-one’
map start 10.0.0.10 end 10.0.0.10 to 1.2.3.4
map start 10.0.0.15 end 10.0.0.15 to 1.2.3.20
map start 10.0.0.100 end 10.0.0.100 to 1.2.3.30
Static mappings are configured according to the map statements. In classic CLI, the map statement can be configured manually by the operator or automatically by the system. In MD-CLI, the map statement must be configured by the operator, but the tools perform nat deterministic calculate-maps command can be used to produce system-generated maps. The calculate-maps command outputs a set of system-generated map statements. The map parameters can then be copied and pasted into an MD-CLI candidate configuration by the operator.
IP addresses from the automatically-generated map statements are sequentially mapped into available outside IP addresses in the pool:
The first inside IP address is mapped to the first available outside IP address from the pool.
The second inside IP address is mapped to the second available outside IP address from the pool.
The following mappings apply to the example above:
Static mappings
10.0.0.0 — 1.2.3.0
10.0.0.1 — 1.2.3.1
10.0.0.2 — 1.2.3.2
10.0.0.3 — 1.2.3.3
10.0.0.4 — 1.2.3.5
10.0.0.5 — 1.2.3.6
:
10.0.0.9 — 1.2.3.10
10.0.0.10 — 1.2.3.4
10.0.0.11 — 1.2.3.11
10.0.0.12 — 1.2.3.12
:
10.0.0.14 — 1.2.3.14
10.0.0.15 — 1.2.3.20
10.0.0.16 — 1.2.3.15
:
10.0.0.19 — 1.2.3.18
10.0.0.20 — 1.2.3.19
10.0.0.21 — 1.2.3.21
:
10.0.0.28 — 1.2.3.28
10.0.0.29 — 1.2.3.29
10.0.0.30 — 1.2.3.31
:
10.0.0.99 — 1.2.3.100
10.0.0.100 — 1.2.3.30
10.0.0.101 — 1.2.3.101
:
10.0.0.255 — 1.2.3.255