> # iSCSI HA with Host Not Having Any Multi-Path Software

> The above topology will not work if the host does not have multi-path software because the host has multiple sessions to the same storage. Without multi-path software the host does not have knowledge of the multiple paths to the same storage.

> IP storage has two additional features that provide an HA solution in this scenario.

> - IPS ports support the VRRP feature
> - IPS has transparent Fibre Channel target failover for iSCSI static virtual targets.

> Statically imported iSCSI targets have an additional option to provide a secondary pWWN for the Fibre Channel target. This can be used when the physical Fibre Channel target is configured to have an LU visible across redundant ports. When the active port fails, the secondary port becomes active and the iSCSI session switches to use the new active port .

> The failover to a secondary port is done transparently by the IPS port without impacting the iSCSI session from the host. All outstanding I/Os are terminated with a check condition status when the primary port fails. New I/Os received during the failover are not completed and receive a busy status.

> Tip If you use LUN mapping, you can define a different secondary Fibre Channel LUN if the LU number is different.

> Enable the optional revert-primary-port option to direct the IPS port to switch back to the primary port when the primary port is up again. If this option is disabled (default) and the primary port is up again after a switchover, the old sessions will remain with the secondary port and do not switch back to the primary port. However, any new session will use the primary port. This is the only situation when both the primary and secondary ports are used at the same time.

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