Technical information

49 EqualLogic Configuration Guide | Version 15.2 | August 2014
9.5 Vertical port failover behavior in PS4100/PS6100 controllers
In PS Series controllers prior to PS4100/6100 families, a link failure or a switch failure was not recognized
as a failure mode by the controller. Thus a failure of a link or an entire switch would reduce bandwidth
available from the array. Referring to Figure 12 or Figure 13, assume that CM0 is the active controller. In
vertical port failover, if CM0 senses a link drop on the local ETH0 port connection path, it will
automatically begin using the ETH0 port on the backup controller (CM1) without incurring a controller
module failover.
Vertical port failover is bi-directional. If CM1 is the active controller then vertical port failover will occur
from CM1 ports to CM0 ports if necessary.