Introduction 1. About This Guide This book describes procedures for configuring fence devices in a Red Hat Cluster using Conga. 2. Audience This book is intended to be used by system administrators managing systems running the Linux operating system. It requires familiarity with Red Hat Enterprise Linux 5 and Red Hat Cluster Suite. 3.
5. Feedback If you spot a typo, or if you have thought of a way to make this manual better, we would love to hear from you. Please submit a report in Bugzilla (http://bugzilla.redhat.com/bugzilla/) against the component rh-cs. Be sure to mention the manual's identifier:...
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Typographic Conventions The above includes a file name, a shell command and a key cap, all presented in Mono-spaced Bold and all distinguishable thanks to context. Key-combinations can be distinguished from key caps by the hyphen connecting each part of a key- combination.
Introduction The mount -o remount file-system command remounts the named file system. For example, to remount the /home file system, the command is mount -o remount /home. To see the version of a currently installed package, use the rpm -q package command.
Notes and Warnings 6.3. Notes and Warnings Finally, we use three visual styles to draw attention to information that might otherwise be overlooked. Note A note is a tip or shortcut or alternative approach to the task at hand. Ignoring a note should have no negative consequences, but you might miss out on a trick that makes your life easier.
Chapter 1. Configuring Fence Devices in a Red Hat Cluster This document provides two configuration examples, showing the steps needed to configure fence devices in a Red Hat cluster using the Conga configuration tool. For general information about fencing and fence device configuration, see Configuring and Managing a Red Hat Cluster. This document includes the procedures for configuring the following two fence devices: •...
Chapter 2. Configuring an APC Switch as a Fence Device This chapter provides the procedures for configuring an APC switch as a fence device in a Red Hat cluster using the Conga configuration tool. Figure 2.1, “Using an APC Switch as a Fence Device” shows the configuration this procedure yields.
Chapter 2. Configuring an APC Switch as a Fence Device Component Name Comment cluster node clusternode2.example.com node in cluster apcclust configured with APC switch to administer power supply cluster node clusternode3.example.com node in cluster apcclust configured with APC switch to administer power supply IP address 10.15.86.96...
APC Fence Device Configuration Procedure Fence Value Description Device Component clusternode2.example.com, and clusternode3.example.com password apcpword password for the APC switch that controls the power for for clusternode1.example.com, clusternode2.example.com, and clusternode3.example.com Table 2.2. Fence Device Components to Configure for APC Fence Device Table 2.3, “Fence Agent Components to Specify for Each Node in apcclust ”...
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Chapter 2. Configuring an APC Switch as a Fence Device 5. At the Add a Sharable Fence Device page, click the drop-down box under Fencing Type and select APC Power Switch. This causes Conga to display the components of an APC Power Figure 2.2, “Adding a Sharable Fence Device”.
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APC Fence Device Configuration Procedure After configuring the APC switch as a shared fence device, use the following procedure to configure the APC switch as the fence device for node clusternode1.example.com 1. At the detailed menu for the cluster apcclust (below the clusters menu), click Nodes. Clicking Nodes causes the display of the status of each node in apcclust.
Chapter 2. Configuring an APC Switch as a Fence Device 6. Click Update main fence properties. This causes a confirmation screen to be displayed. 7. On the confirmation screen, Click OK. A progress page is displayed after which the display returns to the status page for clusternode1.example.com in cluster apcclust.
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Cluster Configuration File with APC Fence Device </clusternode> <clusternode name="clusternode3.example.com" nodeid="3" votes="1"> <fence> <method name="1"/> </fence> </clusternode> </clusternodes> <cman/> <fencedevices/> <rm> <failoverdomains/> <resources/> </rm> </cluster> After the cluster resources and service were configured, the cluster.conf file appears as follows. <?xml version="1.0"?> <cluster alias="apcclust"...
Chapter 2. Configuring an APC Switch as a Fence Device <fencedevices> <fencedevice agent="fence_apc" ipaddr="10.15.86.96" login="apclogin" name="apcfence" passwd="apcpword"/> </fencedevices> <rm> <failoverdomains/> <resources/> </rm> </cluster> 2.5. Testing the APC Fence Device Configuration To check whether the configuration you have defined works as expected, you can use the fence_node to fence a node manually.
Chapter 3. Configuring IPMI Management Boards as Fencing Devices This chapter provides the procedures for configuring IPMI management boards as fencing devices in a Red Hat cluster using the Conga configuration tool. Figure 3.1, “Using IPMI Management Boards as Fence Devices” shows the configuration this procedure yields.
Chapter 3. Configuring IPMI Management Boards as Fencing Devices 3.1. IPMI Fence Device Prerequisite Configuration Table 3.1, “Configuration Prerequisities” summarizes the prequisite components that have been set up before this procedure begins. Component Name Comment cluster ipmiclust three-node cluster cluster node clusternode1.example.com node in cluster ipmiclust configured with IPMI management board and two power supplies IP address 10.15.86.96...
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IPMI Fence Device Components to Configure Fence Value Description Agent Component IP address 10.15.86.96 IP address of the IPMI management board to configure as a fence device for clusternode1.example.com IPMI login ipmilogin login identity for the IPMI management board for clusternode1.example.com password ipmipword...
Chapter 3. Configuring IPMI Management Boards as Fencing Devices Fence Value Description Agent Component authentication password authentication type for the IPMI management board for type clusternode3.example.com Table 3.4. Fence Agent Components to Configure for clusternode3.example.com 3.3. IPMI Fence Device Configuration Procedure This section provides the procedure for adding an IPMI fence device to each node of cluster ipmiclust.
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IPMI Fence Device Configuration Procedure Figure 3.2. Creating an IPMI Fence Device 5. For Name, enter ipmifence1. 6. For IP Address, enter 10.15.86.96. 7. For Login, enter ipmilogin. 8. For Password, enter ipmipword. 9. For Password Script, leave the field blank. 10.
Chapter 3. Configuring IPMI Management Boards as Fencing Devices After configuring an IPMI fence device for clusternode1.example.com, use the following procedure to configure an IPMI fence device for clusternode2.example.com. 1. From the configuration page for clusternode1.example.com, a menu appears on the left of the screen for cluster ipmiclust.
Chapter 4. Troubleshooting The following is a list of some problems you may see regarding the configuration of fence devices as well as some suggestions for how to address these problems. • If your system does not fence a node automatically, you can try to fence the node from the command line using the fence_node command, as described at the end of each of the fencing configuration procedures.
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Chapter 4. Troubleshooting <fence_daemon clean_start="0" post_fail_delay="0" post_join_delay="600"> • If a node fails while the fenced daemon is not running, it will not be fenced. It will cause problems if the fenced daemon is killed or exits while the node is using GFS. If the fenced daemon exits, it should be restarted.
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mygfs 007e0005 none The state of the group should be none. The numbers in the brackets are the node ID numbers of the cluster nodes in the group. The clustat shows which node IDs are associated with which nodes. If you do not see a node number in the group, it is not a member of that group. For example, if a node ID is not in dlm/rgmanager group, it is not using the rgmanager dlm lock space (and probably is not running rgmanager).
Chapter 5. The GFS Withdraw Function When a node can not talk to the rest of the cluster through its normal heartbeat packets, it will be fenced by another node. If a GFS file system detects corruption due to an operation it has just performed, it will withdraw itself.
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