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docs/add_v4_net.md

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+# `add_v4_net` Command
+
+## Name
+
+`add_v4_net`
+
+## Synopsis
+
+```
+add_v4_net ${card} ${vlan} ${group} [{no_ula|isp=abc|no_isp}...]
+```
+
+## Description
+
+Adds an internal network segment with the specified vlan on the specified
+card.  The created vlan-adaptor is put into the specified group.  It is setup
+for IPv4.
+
+The IPv4 network will be a `/24` under `${v4_net_xy0}` if `${card}` is
+`xy0`, for example.  If `${v4_net_xy0}` is not set, then `${v4_net}` is
+used by default.  The 3rd octet will be `$(( ${vlan}/10 + ${vlan}%10 ))`.  For
+example, if `${vlan}` is `102` and `${v4_net}` is `172.18`, then the configured
+v4 network will be `172.18.12.0/24` and the router will hold address
+`172.18.12.1`.  By default, IPv4 network DHCP configuration is enabled and
+the range `.100` to `.200` will be used as a dynamic allocation pool.
+
+Internally, this will call [`add_vlan`](add_vlan.md), passing it `${card}` and
+`${vlan}`.
+
+## See Also
+
+ - [`add_net`](add_net.md)
+ - [`add_v6_net`](add_v6_net.md)
+ - [`add_vlan`](add_vlan.md)