pfSense

On devices with a built in switch changing the switch VLAN mode removes the port state settings from the config resulting in all the ports set as disabled.

This applies when switching from port mode to .1q mode on a clean install or from .1q to port mode on a funtioning .1q setup.

Saving on the ports tab is sufficient to restore the port config which is then applied if rebooted.

Config after switching to .1q mode, adding a vlan and rebooting. From a clean install:

    <switches>
        <switch>
            <device>/dev/etherswitch0</device>
            <vlanmode>DOT1Q</vlanmode>
            <swports></swports>
            <vlangroups>
                <vlangroup>
                    <vgroup>1</vgroup>
                    <vlanid>100</vlanid>
                    <descr></descr>
                    <members>2</members>
                </vlangroup>
            </vlangroups>
        </switch>
    </switches>

After re-saving on the ports tab:

    <switches>
        <switch>
            <device>/dev/etherswitch0</device>
            <vlanmode>DOT1Q</vlanmode>
            <vlangroups>
                <vlangroup>
                    <vgroup>1</vgroup>
                    <vlanid>100</vlanid>
                    <descr></descr>
                    <members>2</members>
                </vlangroup>
            </vlangroups>
            <swports>
                <swport>
                    <port>1</port>
                    <pvid>1</pvid>
                    <state><![CDATA[forwarding]]></state>
                </swport>
                <swport>
                    <port>2</port>
                    <pvid>1</pvid>
                    <state><![CDATA[forwarding]]></state>
                </swport>
                <swport>
                    <port>3</port>
                    <pvid>1</pvid>
                    <state><![CDATA[forwarding]]></state>
                </swport>
                <swport>
                    <port>4</port>
                    <pvid>1</pvid>
                    <state><![CDATA[forwarding]]></state>
                </swport>
                <swport>
                    <port>5</port>
                    <pvid>1</pvid>
                    <state><![CDATA[forwarding]]></state>
                </swport>
            </swports>
        </switch>
    </switches>