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SSHSSH_97332's avatar
SSHSSH_97332
Icon for Nimbostratus rankNimbostratus
Jan 04, 2012

link down-time on failover , what does it mean ?

i cannot understand the below , does this mean that when unit is in standby its interfaces are down ?

 

Specifying the link down-time on failover

 

When configuring a unit of a redundant system configuration, you can use

 

the Link Down Time on Failover setting to specify the amount of time, in

 

seconds, that interfaces for any VLANs on external devices are down when

 

the unit fails over and goes to a standby state. Specifying a value other than

 

0 for this setting causes other vendor switches to use the specified time to

 

learn the MAC address of the newly-active unit.

 

The allowed value for this setting is 0 to 10. Setting the value to 0 disables

 

this setting.

 

config
design

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  • George_Watkins_'s avatar
    George_Watkins_
    Historic F5 Account
    Jan 04, 2012
    This setting is used to trigger a failover based on a VLAN failure for a pair of BIG-IPs configured for high availability. Normally a failover is triggered when a standby BIG-IP loses contact with the active unit. You can see this effect if you pull the serial (or network) failover cable on an HA pair, both will become active units. Normally losing a VLAN will not trigger a failover however this setting allows for that functionality. Hope that clarifies.

     

     

    -George
  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Jan 04, 2012
    you can use the Link Down Time on Failover setting to specify the amount of time, in seconds, that interfaces for any VLANs on external devices are down when the unit fails over and goes to a standby state.when unit fails over to peer, all interfaces will be down for configured seconds in link down time setting.
  • SSHSSH_97332's avatar
    SSHSSH_97332
    Icon for Nimbostratus rankNimbostratus
    Jan 05, 2012
    Thanks , but i'm now confused . is it :

     

     

    when Fail over happens the interfaces will be down on standby unit for this mount of time ?

     

     

    or

     

    Normally losing a VLAN will not trigger a failover however this setting allows for that functionality.

     

  • Michael_Voight_'s avatar
    Michael_Voight_
    Historic F5 Account
    Apr 11, 2014

    It is the amount of time the interfaces on the standby will be down after failover.