Cisco MDS 9000 series Configuration Manual page 133

Chapter 4 Configuring iSCSI
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
IP storage has two additional features that provide an HA solution in this scenario.
•
•
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 (see
Figure 4-16
iSCSI host
iSCSI
In Figure
provide redundant access to the Fibre Channel targets.
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.
If you use LUN mapping, you can define a different secondary Fibre Channel LUN if the LU number is
Tip
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.
To create a static iSCSI virtual target, follow these steps:
Command
Step 1
switch# config terminal
switch(config)#
Step 2
switch(config)# iscsi virtual-target name
iqn.1987-02.com.cisco.initiator
OL-19525-01,Cisco MDS NX-OS Release 4.2(1)
IPS ports support the VRRP feature (see
section on page 6-6) to provide failover for IPS ports.
IPS has transparent Fibre Channel target failover for iSCSI static virtual targets.
Static Target Importing Through Two Fibre Channel Ports
Switch 1
IP
Network
Fibre Channel storage
4-16, you can create an iSCSI virtual target that is mapped to both pWWN1 and pWWN2 to
"Configuring VRRP for Gigabit Ethernet Interfaces"
Figure
Fibre Channel storage
pWWN 1
FC
pWWN 2
Primary access = pWWN1
Secondary access = pWWN 2
ABC
Cisco MDS 9000 Family NX-OS IP Services Configuration Guide
iSCSI High Availability
4-16).
26:00:01:02:03:04:05:06
26:00:01:02:03:10:11:12
Purpose
Enters configuration mode.
Creates the iSCSI target name
iqn.1987-02.com.cisco.initiator.
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