Dynamic LACP Standby Links

Dynamic LACP trunking enables you to configure standby links for a trunk by including more than eight ports in a dynamic LACP trunk configuration. When eight ports (trunk links) are up, the remaining link(s) will be held in standby status. If a trunked link that is “Up” fails, it will be replaced by a standby link, which maintains your intended bandwidth for the trunk. In this example, ports A1 through A9 have been configured for the same LACP trunk. Notice that one of the links shows Standby status, while the remaining eight links are “Up”.

switch# show lacp
                              LACP
       LACP      Trunk    Port                LACP    Admin    Oper
Port   Enabled   Group    Status   Partner   Status   Key      Key
----   -------   -----    ------   -------   ------   ----    -----
Al     Active     Dyn1     Up        Yes     Success   100      100
A2     Active     Dyn1     Up        Yes     Success   100      100
A3     Active     Dyn1     Up        Yes     Success   100      100
A4     Active     Dyn1     Up        Yes     Success   100      100
A5     Active     Dyn1     Up        Yes     Success   100      100
A6     Active     Dyn1     Up        Yes     Success   100      100
A7     Active     Dyn1     Up        Yes     Success   100      100
A8     Active     Dyn1     Up        Yes     Success   100      100
A9     Active     Dyn1    Standby    Yes     Success   100      100