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Thong_196816's avatar
Thong_196816
Icon for Nimbostratus rankNimbostratus
May 25, 2015

network failover/serial cable for HA

for HA configurations, there are 3 options   network failover in network failover the heartbeat is the network packet   serial failover serial cable failover is just checking a vo...
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  • nitass_89166's avatar
    nitass_89166
    May 25, 2015

    network and Serial failover

     

    If you configure a BIG-IP high-availability pair to use network failover, and the hardwired failover cable also connects the two units, hardwired failover always has precedence; if network failover traffic is compromised, the two units do not fail over because the hardwired failover cable still connects them.

     

    sol2397: Comparison of hardwired failover and network failover features

     

    https://support.f5.com/kb/en-us/solutions/public/2000/300/sol2397.html

     

svs's avatar
svs
Icon for Cirrostratus rankCirrostratus
May 25, 2015

Hi Thong,

 

do not use the hardwired failover except you need failover times under 1 second. There is so much to keep in mind when the hardwired failover is used. For example, that in most cases there will be no failover during a reboot of a node. Also, as nitass already stated, there will be no software failover as long as the secondary node is still physically available through the serial cable.

 

In my mind the hardwired failover doesn't make sense at all. There may be cases, where it makes perfect sense, but I'm pretty sure those cases are rare. I removed the hardwired failover on every single customer installation. Since there is no hardwired failover software updates are working as expected.

 

Greets, svs