I recently played with VLANs and screwed up it's switching capability
exactly as you say.
I managed to fix it by restoring the default setup in /etc/config/network
(Especially config switch_vlan and ports)

Compare your /etc/config/network with what I have (and works):
config switch
        option name     rtl8366s
        option reset    1
        option enable_vlan 0
        # Blinkrate: 0=43ms; 1=84ms; 2=120ms; 3=170ms; 4=340ms; 5=670ms
        option blinkrate        2
        option max_length 3

config switch_vlan
        option device   rtl8366s
        option vlan     1
        option ports    "0 1 2 3 5t"

config switch_port
        # Port 1 controls the GREEN configuration of LEDs for
        # the switch and the section does not correspond to a real
        # switch port.
        #
        # 0=LED off; 1=Collision/FDX; 2=Link/activity; 3=1000 Mb/s;
        # 4=100 Mb/s; 5=10 Mb/s; 6=1000 Mb/s+activity; 7=100 Mb/s+activity;
        # 8=10 Mb/s+activity; 9=10/100 Mb/s+activity; 10: Fiber;
        # 11: Fault; 12: Link/activity(tx); 13: Link/activity(rx);
        # 14: Link (master); 15: separate register

        option device           rtl8366s
        option port             1
        option led              6

config switch_port
        # Port 2 controls the ORANGE configuration of LEDs for
        # the switch and the section does not correspond to a real
        # switch port.
        #
        # See the key above for switch port 1 for the meaning of the
        # 'led' setting below.

        option device           rtl8366s
        option port             2
        option led              9

config switch_port
        # Port 5 controls the configuration of the WAN LED and the
        # section does not correspond to a real switch port.
        #
        # To toggle the use of green or orange LEDs for the WAN port,
        # see the LED setting for wndr3700:green:wan in /etc/config/system.
        #
        # See the key above for switch port 1 for the meaning of the
        # 'led' setting below.

        option device           rtl8366s
        option port             5
        option led              2

Best regards,
Maciej Soltysiak

On Wed, Feb 20, 2013 at 5:01 PM, William Katsak <wkatsak@gmail.com> wrote:

> Hello,
>
> Just wanted to see if anyone has seen an issue like this:
>
> I have a 3800 running Sugarland at a remote site. It was running nice and
> reliably, connected to the local network by a VLAN trunked connection (I
> have interfaces for the default VLAN, and VLANS 100 and 200 passing
> through). Last night it suddenly stopped working. There seems to be no data
> flowing through the switch at all, even though I can ssh to the router,
> reboot, poke at it, etc. from over the Internet.
>
> I see no error messages regarding the switch in the logs or dmesg. Anyone
> else see a 3800 switch crap out unceremoniously?
>
> Thanks,
> Bill Katsak
>
>
>
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