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+This target is only valid in the
+.B nat
+table, in the
+.B POSTROUTING
+and
+.B INPUT
+chains, and user-defined chains which are only called from those
+chains. It specifies that the source address of the packet should be
+modified (and all future packets in this connection will also be
+mangled), and rules should cease being examined. It takes the
+following options:
+.TP
+\fB\-\-to\-source\fP [\fIipaddr\fP[\fB\-\fP\fIipaddr\fP]][\fB:\fP\fIport\fP[\fB\-\fP\fIport\fP]]
+which can specify a single new source IP address, an inclusive range
+of IP addresses. Optionally a port range,
+if the rule also specifies one of the following protocols:
+\fBtcp\fP, \fBudp\fP, \fBdccp\fP or \fBsctp\fP.
+If no port range is specified, then source ports below 512 will be
+mapped to other ports below 512: those between 512 and 1023 inclusive
+will be mapped to ports below 1024, and other ports will be mapped to
+1024 or above. Where possible, no port alteration will occur.
+In Kernels up to 2.6.10, you can add several \-\-to\-source options. For those
+kernels, if you specify more than one source address, either via an address
+range or multiple \-\-to\-source options, a simple round-robin (one after another
+in cycle) takes place between these addresses.
+Later Kernels (>= 2.6.11-rc1) don't have the ability to NAT to multiple ranges
+anymore.
+.TP
+\fB\-\-random\fP
+If option
+\fB\-\-random\fP
+is used then port mapping will be randomized (kernel >= 2.6.21).
+.TP
+\fB\-\-persistent\fP
+Gives a client the same source-/destination-address for each connection.
+This supersedes the SAME target. Support for persistent mappings is available
+from 2.6.29-rc2.
+.PP
+Kernels prior to 2.6.36-rc1 don't have the ability to
+.B SNAT
+in the
+.B INPUT
+chain.
+.TP
+IPv6 support available since Linux kernels >= 3.7.