1

If I connect my switch to two upstream feeds from my ISP, my internal LAN stops functioning (see illustration below).

What is it in the TCP/IP protocol that is disrupted to cause the above?

                 +--------+
                 |        |
        +>>>>>>>>+        +>>>>>>>>>>> LAN machine 1 (not working normally)
        ^        |        +
ISP >>>>+        | switch +
        v        |        +
        +>>>>>>>>+        +>>>>>>>>>>> LAN machine 2 (not working normally)
                 |        |
                 +--------+
boardrider
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1 Answers1

1

Two scenario possible:

  1. Configure the spanning-tree protocol please to prevent a network loop if both link send the same feed.

  2. Configure the switch with some VLAN to isolate the LAN from the WAN.

yagmoth555
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