Oracle DE2-24, Руководство по обслуживанию клиентов

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Rolling Back System Software
upgraded. For clusters with at least one active pool on each controller, these restrictions
mean that disk shelf firmware upgrade can be performed only by a controller that is in the
"owner" state.
During the firmware upgrade process, hardware may appear to be removed and inserted, or
offlined and onlined. While alerts attributed to these actions are suppressed, if you are viewing
the Maintenance > Hardware screen or the Configuration > Storage screen, you may see the
effects of these upgrades in the UI in the form of missing or offline devices. This is not a cause
for concern; however, if a device remains offline or missing for an extended period of time
(several minutes or more) even after refreshing the hardware view, this may be an indication
of a problem with the device. Check the Maintenance > Problems view for any relevant faults
that may have been identified. Additionally, in some cases, the controllers in the disk shelves
may remain offline during firmware upgrade. If this occurs, no other controllers are updated
until this condition is fixed. If an enclosure is listed as only having a single path for an extended
period of time, check the physical enclosure to determine whether the green link lights on the
back of the SIM or IOM are active. If not, remove and re-insert the SIM or IOM to re-establish
the connection. Verify that all enclosures are reachable by two paths.
Rolling Back System Software
The rollback procedure reverts all of the system software and all of the metadata settings of
the system back to their state just prior to applying an update. This feature is implemented by
taking a snapshot of various aspects of the system before the new update is applied, and rolling
back this snapshot to implement the rollback. The implications of rollback are as follows:
■
Any appliance configuration changes are reverted and lost. For example, assume you are
running version V, and then you update to V+1, and then you change your DNS server. If
you execute a rollback, then your DNS server setting modification is effectively undone and
removed from the system permanently.
■
Conversely, any changes made to user data are
not
reverted: if you update from V to V+1,
and clients then create directories or modify shares in any way, those changes still exist after
the rollback (as you would expect).
■
If the appliance is running version V, and has previous rollback targets V-1 and V-2, and
you revert all the way to version V-2 (thereby "skipping" V-1), then you not only are
removing the system software settings and system software for V, but also for V-1. That is,
after a rollback to V-2, it is as if updates V-1 and V never happened. However, the software
upload images for V-1 and V are saved on the system, and you can apply them again after
the rollback, if you wish, by re-executing the update.
If after applying an update, the system is back up and running, you can use either the BUI or the
CLI to initiate a rollback to one of two previously applied updates. If the system is not able to
run at all after an update, then use the fail-safe rollback procedure.
Maintaining the System 309