5.2. Starting the Cluster Configuration Tool
ssh -Ycommand and issuing the
system-config-clustercommand. For example, to start the Cluster Configuration Tool on cluster node nano-01, do the following:
- Log in to a cluster node and run
system-config-cluster. For example:
ssh -Y root@nano-01. . . #
- If this is the first time you have started the Cluster Configuration Tool, the program prompts you to either open an existing configuration or create a new one. Click to start a new configuration file (refer to Figure 5.1, “Starting a New Configuration File”).
Figure 5.1. Starting a New Configuration File
NoteThe Cluster Configuration Tool, exit, and restart the Red Hat Cluster Suite management GUI (tab for the Red Hat Cluster Suite management GUI is available after you save the configuration file with the
system-config-cluster). (The tab displays the status of the cluster service manager, cluster nodes, and resources, and shows statistics concerning cluster service operation. To manage the cluster system further, choose the tab.)
- Clicking New Configuration dialog box to be displayed (refer to Figure 5.2, “Creating A New Configuration”). The New Configuration dialog box provides a text box for cluster name and the following checkboxes: and . In most circumstances you only need to configure the cluster name.causes the
NoteChoose the cluster name carefully. The only way to change the name of a Red Hat cluster is to create a new cluster configuration with the new name.
Custom Configure MulticastRed Hat Cluster software chooses a multicast address for cluster management communication among cluster nodes. If you need to use a specific multicast address, click thecheckbox and enter a multicast address in the text boxes.
NoteIPV6 is not supported for Cluster Suite in Red Hat Enterprise Linux 5.If you do not specify a multicast address, the Red Hat Cluster software (specifically,
cman, the Cluster Manager) creates one. It forms the upper 16 bits of the multicast address with 239.192 and forms the lower 16 bits based on the cluster ID.
NoteThe cluster ID is a unique identifier that
cmangenerates for each cluster. To view the cluster ID, run the
cman_tool statuscommand on a cluster node.If you do specify a multicast address, you should use the 239.192.x.x series that
cmanuses. Otherwise, using a multicast address outside that range may cause unpredictable results. For example, using 224.0.0.x (which is "All hosts on the network") may not be routed correctly, or even routed at all by some hardware.
NoteIf you specify a multicast address, make sure that you check the configuration of routers that cluster packets pass through. Some routers may take a long time to learn addresses, seriously impacting cluster performance.
Use a Quorum DiskIf you need to use a quorum disk, click the Table 5.1, “Quorum-Disk Parameters” describes the parameters.checkbox and enter quorum disk parameters. The following quorum-disk parameters are available in the dialog box if you enable : , , , , , , and .
ImportantQuorum-disk parameters and heuristics depend on the site environment and 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.
NoteIt is probable that configuring a quorum disk requires changing quorum-disk parameters after the initial configuration. The Cluster Configuration Tool (
system-config-cluster) provides only the display of quorum-disk parameters after initial configuration. If you need to configure quorum disk, consider using Conga instead; Conga allows modification of quorum disk parameters.Overall:While
system-config-clusterprovides several convenient tools for configuring and managing a Red Hat Cluster, the newer, more comprehensive tool, Conga, provides more convenience and flexibility than
system-config-cluster. You may want to consider using Conga instead (refer to Chapter 3, Configuring Red Hat Cluster With Conga and Chapter 4, Managing Red Hat Cluster With Conga).
Figure 5.2. Creating A New Configuration
- When you have completed entering the cluster name and other parameters in the New Configuration dialog box, click . Clicking starts the Cluster Configuration Tool, displaying a graphical representation of the configuration (Figure 5.3, “The Cluster Configuration Tool”).
Figure 5.3. The Cluster Configuration Tool
Table 5.1. Quorum-Disk Parameters
|Enables quorum disk. Enables quorum-disk parameters in the New Configuration dialog box.|
|The frequency of read/write cycles, in seconds.|
|The number of cycles a node must miss in order to be declared dead.|
|The number of votes the quorum daemon advertises to CMAN when it has a high enough score.|
| The minimum score for a node to be considered "alive". If omitted or set to 0, the default function, |
|The storage device the quorum daemon uses. The device must be the same on all nodes.|
| Specifies the quorum disk label created by the |