HP 3PAR Operating System Software User Manual

Page 268

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Table 15 Quorum Status Qualifiers (continued)

Description

Quorum Status Qualifier

is either in the Initializing state, or is not sufficiently
far enough into its Re-starting system stability checks
to consider auto-advance to the Starting state.

A target failure, one of the side effects of a storage system
failure, is one of the criteria evaluated when making a
decision to perform a peer-persistence failover.

Target not ready

A quorum cannot advance beyond the Initializing
or Re-starting state if the RC target it is associated with
is not ready.

A quorum announcer process runs on each node of the
storage system. Individual quorum announcer processes

Below min safe num QAs

regularly update the QW with the operational status of the
given node. These processes each individually sample the
QW database for updates from the mirror system to
determine the operational status of the remote system.

The multiple quorum-announcer processes provide a level
of redundancy in communication, cross-quorum
configuration, and status consistency checking; they also
provide decision confirmation.

The system is configured to prevent the quorum from
advancing beyond the Initializing or Re-starting
states, or to reset the quorum if the number of active QA
processes drops locally, on a given storage system, below
the minimum safe number of QAs. The minimum safe
number of QAs is set to two.

The quorum-announcer processes must be seeded with
quorum-specific details to be appended to the updates sent

Not all QAs configured

to the QW. All operational QA processes must be
configured for the given quorum.

If one or more QA process is not configured for a given
quorum, the quorum will be prevented from advancing
beyond the Initializing or Re-starting states, or
will be reset if already in the Started state.

This general catchall qualifier is used when there are issues
with the configuration or stability of the remote half of the

Quorum not stable

quorum that are best diagnosed on the partner system itself.
Check the configuration, quorum status, and qualifier on
the remote system.

The HP 3PAR Peer-Persistence failover solution pivots on
detecting the lack of updates from the remote storage

QA config inconsistent

system to the quorum witness. Accordingly, the rate at
which updates are posted and the rate at which the remote
status is polled is crucial to the correct operation of the
system. The storage systems periodically check these update
and polling rate settings.

If the configuration settings for this quorum are not
consistent across all QA processes on both storage systems,
then the quorum will be prevented from advancing beyond
the Initializing or Re-starting states, or will be
reset if it is already in the Started state.

Status-related checks are performed both locally, across
the quorum-announcer processes so as to ensure that they

QA status inconsistent

are consistently configured, and also between the two
storage systems.

268 HP 3PAR Quorum Witness Deployment

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