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  1. #1

    How to configure Link Backup on TL-ER5120 V3

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    ISP : [/COLOR]

    Hello everybody !

    I have another problem yet, with link backup now...

    I try to configure Link Backup on a router TL-ER5120...
    I would like to when connection on WAN1 failed, WAN2 replace WAN1 !

    I have searched on internet and forum, but I don't find the solution.

    Here you can see the installation :

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    In a normal mode, the traffic is on WAN1 -> it's ok.

    Now here is my configuration for link backup :

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    for online detection WAN 1 :
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    for online detection WAN 2 :
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    and for load balancing (I desactivate all... I don't want do use it) :
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    It works fine when I play with option connect/disconnect from WAN1&2 parameters.
    Or if I physically connect/disconnect WAN 1 or 2

    BUT :

    if I lose the connection on the WAN 1, I want to say :
    - line ADSL is off
    - but the modem ADSL is always ON and connected in the WAN 1 port
    now the router doesn't switch on the port WAN 2.

    I can see in the "Online detection" menu that WAN1 is well offline (and WAN 2 is online)
    But I can't access internet.
    If I go on the WAN 1 parameters and I click on disconnect button, so WAN 2 take the connection and I access internet.

    I try to play with DNS off WAN ports, with parameters in online detection menu (specify IP or DNS lookup), but nothing works.

    I despair, I don't understand why if I disconnect manually WAN 1 (with cable or with button in WAN parameters) it works !!!
    And not automatically ????!!!!!

    I hop you have an idea !!!

    Thanks very much for your help !!!
    Attached Images  

  2. #2
    Hi jjacques68 ;-)

    It should be help you : http://forum.tp-link.com/showthread....l=1#post228910

    With my actual params, if I broke the adsl input (modem 1), the TP-link is correctly switch to the second modem (dns is working !).... but it's not excactly what I was expecting at first (I whould like a real Link Backup) because it's a load balancing conf ;-(

  3. #3
    I think maybe it comes to dns issue. Why not configure wan1's DNS server as and have a try.

  4. #4
    Another attempt, keep your settings. When WAN1 is offline and WAN2 is online, you mean cann't get online. Now set your PC's dns server as If you could get Internet?
    Last edited by fearthebeard; 02-12-2018 at 07:26.


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