IBM System storage DS6000 Series, Attachment Manual

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Each device shows 0x30001 as a reservation key. You must issue the scu
command again to remove the persistent reserve using reservation key 0x30001 on
each node. Tru64 places a unique reservation key on each LUN whenever the
storage unit assigns the LUN. The reservation key can only be removed from that
specific host to which it is assigned. Because it is not possible to tell exactly which
registrant on the host holds the reservation, you must issue an scu clear command
on each node in the cluster. Figure 21 shows an example of what you see when
you use the scu clear command.
One of the two commands that you see in Figure 21 clears the persistent reserve
on storage unit volume 10a-21380.
Use the scu command to check reservations. Figure 22 on page 40 shows an
example of what you see when you use the scu command again.
One of the two commands you see in Figure 22 on page 40 clears the persistent
reserves on storage unit volume 10a-21380.
alpha2> scu –f /dev/rdisk/dsk47c show reservations
Persistent Reservation Header:
Generation Value: 49
Additional Length: 16
Reservation Descriptors:
Reservation Key: 0x30001
Scope-Specific Address: 0
Reservation Type: 0x5 (Write Exclusive Registrants Only)
Reservation Scope: 0 (LU - full logical unit)
Extent Length: 0
Figure 20. Example of the scu command
alpha1> scu –f /dev/rdisk/dsk47c press clear key 0x30001
alpha2> scu –f /dev/rdisk/dsk47c press clear key 0x30001
Figure 21. Example of the scu clear command
Chapter 4. Attaching to a Hewlett-Packard AlphaServer Tru64 UNIX host
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