1 This target is only valid in the 2 .B nat 3 table, in the 4 .B POSTROUTING 5 chain. It should only be used with dynamically assigned IP (dialup) 6 connections: if you have a static IP address, you should use the SNAT 7 target. Masquerading is equivalent to specifying a mapping to the IP 8 address of the interface the packet is going out, but also has the 9 effect that connections are 10 .I forgotten 11 when the interface goes down. This is the correct behavior when the 12 next dialup is unlikely to have the same interface address (and hence 13 any established connections are lost anyway). 14 .TP 15 \fB\-\-to\-ports\fP \fIport\fP[\fB\-\fP\fIport\fP] 16 This specifies a range of source ports to use, overriding the default 17 .B SNAT 18 source port-selection heuristics (see above). This is only valid 19 if the rule also specifies one of the following protocols: 20 \fBtcp\fP, \fBudp\fP, \fBdccp\fP or \fBsctp\fP. 21 .TP 22 \fB\-\-random\fP 23 Randomize source port mapping 24 If option 25 \fB\-\-random\fP 26 is used then port mapping will be randomized (kernel >= 2.6.21). 27 .TP 28 IPv6 support available since Linux kernels >= 3.7. 29