Installation guide

4. Q u o ru m Part it io n tab — This tab provides an interface for configuring these Q u o ru m
Part it io n Co n f ig u rat io n parameters: Do n o t u se a Q u o ru m Part it io n , Use a Q u o ru m
Part it io n , In t erval, Vot es, T KO , Min imum Sco re, Device, Lab el, and Heu rist ics. The
Do n o t u se a Q u o ru m Part it io n parameter is enabled by default. Table 3.1, “Quorum-Disk
Parameters” describes the parameters. If you need to use a quorum disk, click U se a
Q u o ru m Part it io n , enter quorum disk parameters, click Apply, and restart the cluster for
the changes to take effect.
Important
Quorum-disk parameters and heuristics depend on the site environment and the
special requirements needed. To understand the use of quorum-disk parameters and
heuristics, refer to the qdisk(5) man page. If you require assistance understanding and
using quorum disk, contact an authorized Red Hat support representative.
Note
Clicking Ap p ly on the Q u o ru m Part it io n tab propagates changes to the cluster
configuration file (/etc/cluster/cluster.conf) in each cluster node. However, for
the quorum disk to operate, you must restart the cluster (refer to Section 4.1, “Starting,
Stopping, and Deleting Clusters”).
T ab le 3.1. Q u o ru m- D isk Paramet ers
Paramet er Descrip t io n
Do n o t u se a
Q u o ru m Part it io n
Disables quorum partition. Disables quorum-disk parameters in the
Q u o ru m Part it io n tab.
Use a Q u o ru m
Part it io n
Enables quorum partition. Enables quorum-disk parameters in the
Q u o ru m Part it io n tab.
In t erval The frequency of read/write cycles, in seconds.
Vo t es The number of votes the quorum daemon advertises to CMAN when it has
a high enough score.
T K O The number of cycles a node must miss to be declared dead.
Min imum Sco re The minimum score for a node to be considered "alive". If omitted or set to
0, the default function,
floor((n+1)/2)
, is used, where
n
is the sum of
the heuristics scores. The Min imum Sco re value must never exceed the
sum of the heuristic scores; otherwise, the quorum disk cannot be
available.
Device The storage device the quorum daemon uses. The device must be the
same on all nodes.
Lab el Specifies the quorum disk label created by the
mkqdisk
utility. If this field
contains an entry, the label overrides the Device field. If this field is used,
the quorum daemon reads
/proc/partitions
and checks for qdisk
signatures on every block device found, comparing the label against the
specified label. This is useful in configurations where the quorum device
name differs among nodes.
Red Hat Ent erprise Linux 5 Clust er Administ rat ion
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