Installation guide

You can configure the Red Hat High-Availability Add-On to use UDP unicast by setting the cman
transpo rt= "ud pu" parameter in the cl uster. co nf configuration file. You can also specify
Unicast from the Net wo rk Co n f ig u rat io n page of the Co n g a user interface, as described in
Section 3.5.3, “ Network Configuration” .
2.13. Considerat ions for ri cci
For Red Hat Enterprise Linux 6, ri cci replaces ccsd. Therefore, it is necessary that ri cci is
running in each cluster node to be able to propagate updated cluster configuration whether it is via
the cman_to o l versi o n -r command, the ccs command, or the lu ci user interface server. You
can start ricci by using servi ce ri cci start or by enabling it to start at boot time via
chkco nfi g . For information on enabling IP ports for ricci , refer to Section 2.3.1, “ Enabling IP
Ports on Cluster Nodes” .
For the Red Hat Enterprise Linux 6.1 release and later, using ri cci requires a password the first time
you propagate updated cluster configuration from any particular node. You set the ri cci password
as root after you install ri cci on your system. To set this password, execute the passwd ri cci
command, for user ricci .
2.14 . Configuring Virt ual Machines in a Clust ered Environment
When you configure your cluster with virtual machine resources, you should use the rg manag er
tools to start and stop the virtual machines. Using vi rsh to start the machine can result in the virtual
machine running in more than one place, which can cause data corruption in the virtual machine.
To reduce the chances of administrators accidentally "double-starting" virtual machines by using
both cluster and non-cluster tools in a clustered environment, you can configure your system by
storing the virtual machine configuration files in a non-default location. Storing the virtual machine
configuration files somewhere other than their default location makes it more difficult to accidentally
start a virtual machine using vi rsh, as the configuration file will be unknown out of the box to
vi rsh.
The non-default location for virtual machine configuration files may be anywhere. The advantage of
using an NFS share or a shared GFS2 file system is that the administrator does not need to keep the
configuration files in sync across the cluster members. However, it is also permissible to use a local
directory as long as the administrator keeps the contents synchronized somehow cluster-wide.
In the cluster configuration, virtual machines may reference this non-default location by using the
path attribute of a virtual machine resource. Note that the path attribute is a directory or set of
directories separated by the colon ':' character, not a path to a specific file.
Warning
The l i bvi rt-g uests service should be disabled on all the nodes that are running
rg manager. If a virtual machine autostarts or resumes, this can result in the virtual machine
running in more than one place, which can cause data corruption in the virtual machine.
For more information on the attributes of a virtual machine resources, refer to Table B.26, “ Virtual
Machine (vm Resource)” .
⁠Chapt er 2 . Before Configuring t he Red Hat High Availabilit y Add- O n
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