| This target is only valid in the |
| .B nat |
| table, in the |
| .B POSTROUTING |
| chain. It should only be used with dynamically assigned IP (dialup) |
| connections: if you have a static IP address, you should use the SNAT |
| target. Masquerading is equivalent to specifying a mapping to the IP |
| address of the interface the packet is going out, but also has the |
| effect that connections are |
| .I forgotten |
| when the interface goes down. This is the correct behavior when the |
| next dialup is unlikely to have the same interface address (and hence |
| any established connections are lost anyway). It takes one option: |
| .TP |
| \fB\-\-to\-ports\fP \fIport\fP[\fB\-\fP\fIport\fP] |
| This specifies a range of source ports to use, overriding the default |
| .B SNAT |
| source port-selection heuristics (see above). This is only valid |
| if the rule also specifies |
| \fB\-p tcp\fP |
| or |
| \fB\-p udp\fP. |
| .TP |
| \fB\-\-random\fP |
| Randomize source port mapping |
| If option |
| \fB\-\-random\fP |
| is used then port mapping will be randomized (kernel >= 2.6.21). |
| .RS |
| .PP |
