About setting up disk-based I/O fencing | Symantec 5 guide

Configuring VCS clusters for data integrity	89
About setting up disk-based I/O fencing

Disks that act as coordination points are called coordinator disks. Coordinator disks are three standard disks or LUNs set aside for I/O fencing during cluster reconfiguration. Coordinator disks do not serve any other storage purpose in the VCS configuration.

You can configure coordinator disks to use Veritas Volume Manager Dynamic Multipathing (DMP) feature. Dynamic Multipathing (DMP) allows coordinator disks to take advantage of the path failover and the dynamic adding and removal capabilities of DMP. So, you can configure I/O fencing to use either DMP devices or the underlying raw character devices. I/O fencing uses SCSI-3 disk policy that is either raw or dmp based on the disk device that you use. The disk policy is raw by default. Symantec recommends using the DMP disk policy.

See the Veritas Volume Manager Administrator’s Guide.

About setting up disk-based I/O fencing

Figure 5-1illustrates the tasks involved to configure I/O fencing.

Image 89

Symantec 5 manual About setting up disk-based I/O fencing, 1illustrates the tasks involved to configure I/O fencing

Contents

Veritas Cluster Server Installation Guide Legal Notice Veritas Cluster Server Installation Guide Symantec Corporation Ellis Street Mountain View, CA Contacting Technical Support Technical Support Documentation feedback Customer serviceLicensing and registration Additional enterprise services Maintenance agreement resources Contents Contents Chapter Configuring VCS clusters for data integrity 121 Chapter Adding and removing cluster nodes Index 173 171 Contents This chapter includes the following topics About Veritas Cluster ServerAbout VCS basics Example of a four-node VCS cluster About multiple nodesAbout shared storage About network channels for heartbeating See About the LLT and GAB configuration files onAbout LLT and GAB About VCS seeding About preexisting network partitions Veritas Installation Assessment Service About VCS featuresAbout VCS notifications About global clusters You can add the following optional components to VCS About VCS optional componentsAbout I/O fencing About Symantec Product Authentication Service AT See Installing the Java Console on See Preparing to configure the clusters in secure mode onAbout Cluster Manager Java Console About Veritas Cluster Server Management Console About VCS optional components Page 1lists the hardware requirements for a VCS cluster About planning to install VCSHardware requirements Description Required disk spaceHardware requirements for a VCS cluster Kernel Architecture Supported operating systems Rhel Required Linux RPMs for VCS Supported software Planning to install VCS Supported software Preparing to configure the clusters in secure mode About preparing to install VCS 1depicts the flow of configuring VCS cluster in secure mode Workflow to configure VCS cluster in secure mode This task Preparatory tasks to configure a cluster in secure modeTasks # ./installer Installing the root broker for the security infrastructureSee About Symantec Product Authentication Service AT on Venus # vssat showprpl --pdrtype root \ Venus # vssat showalltrustedcreds Venus # vssat showbrokerhash Creating encrypted files for the security infrastructure Addprpl command RootBroker # vssat createpkg \ For example Performing preinstallation tasks Https//licensing.symantec.com Obtaining VCS license keysTask Reference You can use network switches instead of hubs Setting up the private networkPage See About installing and configuring VCS on Configuring SuSE network interfaces Where ethX is the interface name For example Run the command# cd /etc/sysconfig # ifconfig -a # cd /etc/sysconfig/network Setting up inter-system communication# ifconfig eth0 # ssh-keygen -t dsa Setting up ssh on cluster systemsAccept the default location of ~/.ssh/iddsa See About setting up disk-based I/O fencing on Setting up shared storage# chmod 755 ~/.ssh # exec /usr/bin/ssh-agent $SHELL # ssh-add For the C Shell csh or tcsh, type Setting the Path variableSetting the Manpath variable Case of a panic, the node will reboot after 10 seconds Setting the kernel.panic tunableOptimizing LLT media speed settings on private NICs # mount -o ro /dev/cdrom /mnt/cdrom Performing automated pre-installation checkMounting the product disc # ./installvcs -precheck galaxy nebula VCS About installing and configuring VCS Example vcscluster27 To configure Veritas Cluster Server you needExample galaxy, nebula Var/tmp/privatedir/roothash To configure VCS clusters in secure mode optional, you needTo configure Smtp email notification optional, you need Optional VCS RPMs To configure Snmp trap notification optional, you needTo configure global clusters optional, you need Optional features of the installvcs program About the VCS installation programVRTSvcsmn Manual pages for VCS commands See About preparing to install VCS on About installvcs program command options Interacting with the installvcs programInstallvcs command usage takes the following form Optional action Reference Installvcs system1 system2... options Nooptionalpkgs Option and Syntax Description Configuring VCS using configure option Installing VCS using installonly option See Configuring the basic cluster on Installing and configuring VCS 5.0 RU33lists the installation and the configuration tasks Overview of tasks Starting the software installation Start the installvcs program Specifying systems for installation# ./installvcs -rsh # cd /clusterserver See Checking licensing information on the system on Licensing VCS Enter keys for additional product features Choosing VCS RPMs for installation Choosing to install VCS RPMs or configure VCS See Configuring VCS using configure option on Starting the software configuration Configuring the basic cluster Specifying systems for configuration# ./installvcs -configure # cd /dvdrom/clusterserverPage Configuring the cluster in secure mode Symantecexample.com East.symantecexample.comRoot@east.symantecexample.com Root/roothash Enter the user’s name, password, and level of privileges Configuring Smtp email notificationAdding VCS users To add a user, enter y at the prompt See Configuring Snmp trap notification on See Configuring global clusters on Configuring Snmp trap notificationIf you do not want to add, answer n Verify and confirm the Smtp notification information Verify and confirm the Snmp notification information Configuring global clusters See Creating VCS configuration files on Installing VCS RPMs Verifying the NIC configuration Creating VCS configuration files Set the Persistentname for all the NICs Completing the installationStarting VCS File description VCS node authentication broker Software requirements for the Java Console Installing the Java ConsoleHardware requirements for the Java Console See Software requirements for the Java Console on Installing the Java Console on a Windows system Installing the Java Console on Linux for IBM PowerNavigate to the folder that contains the RPMs # cd /mnt/cdrom/distarch/clusterserver/rpms Installing VCS Simulator on Unix systems Installing VCS SimulatorInstalling VCS Simulator on Windows systems Software requirements for VCS Simulator Reviewing the installation See About verifying the VCS installation on Verifying the cluster after installationVerifying and updating licenses on the system Checking licensing information on the system Replacing a VCS demo license with a permanent license Updating product licenses using vxlicinst# cd /opt/VRTS/bin # hastop -all -force To access the VCS documentation Accessing the VCS documentationStart VCS on each node # hastart About configuring VCS clusters for data integrity Configuring VCS clusters for data integrity About data disks About I/O fencing componentsAbout coordination points See About data disks on 1illustrates the tasks involved to configure I/O fencing About setting up disk-based I/O fencing Workflow to configure disk-based I/O fencing I/O fencing configuration files include Preparing to configure disk-based I/O fencing # fdisk -l Initializing disks as VxVM disks Libnamevidpid # vxddladm listsupport all Example specifies the CDS format Identifying disks to use as coordinator disksChecking shared disks for I/O fencing See Testing the disks using vxfentsthdw utility on Verifying that the nodes have access to the same diskTesting the shared disks for SCSI-3 # /opt/VRTSvcs/vxfen/bin/vxfentsthdw Testing the disks using vxfentsthdw utilitySee Removing permissions for communication on Dev/sdr If you use rsh for communication# /opt/VRTSvcs/vxfen/bin/vxfentsthdw -n Setting up coordinator disk groups Setting up disk-based I/O fencing manually# vxdg init vxfencoorddg sdx sdy sdz # vxdg -g vxfencoorddg set coordinator=on Deport the coordinator disk group Creating I/O fencing configuration filesFor raw device configuration Stop VCS on all nodes Modifying VCS configuration to use I/O fencingMake a backup copy of the main.cf file # hacf -verify /etc/VRTSvcs/conf/config Verifying I/O fencing configurationStart VCS # /etc/init.d/vxfen start # vxfenadm -d Removing permissions for communicationPage About the LLT and GAB configuration files About verifying the VCS installation Galaxy Nebula About the VCS configuration file main.cf Sample main.cf file for VCS clusters Page Sample main.cf file for global clusters ClusterAddress = Application wac IP gcoip NIC csgnic Gcoip requires csgnicWac requires gcoip Verify the content of the configuration files Verifying the LLT, GAB, and VCS configuration filesSee Setting the Path variable on Verifying LLT, GAB, and cluster operation See Verifying the cluster on Verifying LLTOutput on galaxy resembles Output on nebula resembles Eth1 UP Output resembles Verifying GAB Verifying the cluster Verifying the cluster nodes Current Eth1 UP eth2 UP Adding a node to a cluster About adding and removing nodes See Adding a license key on Setting up the hardware Preparing for a manual installation when adding a node See Mounting the product disc on Installing VCS RPMs for a manual installation SLES10/ppc64, required Rpms Adding a license keyChecking licensing information on the system See Configuring LLT and GAB on Setting up the node to run in secure modeSee Configuring the authentication broker on node saturn on See Setting up VCS related security configuration on Configuring the authentication broker on node saturn Setting up VCS related security configuration Configuring LLT and GAB If the file on one of the existing nodes resembles On the new system, run the command# /sbin/lltconfig -c Add the new system to the cluster To verify GAB On the new node, run the commandAdding the node to the existing cluster Starting VCS and verifying the cluster Removing a node from a clusterStop VCS on the new node Start VCS on the new node Verifying the status of nodes and service groups # hastatus -summary Deleting the departing node from VCS configurationCheck the status of the systems and the service groups # haconf -makerw # hagrp -unlink grp4 grp1 # hagrp -switch grp3 -to nebula# hagrp -dep Check the status Save the configuration, making it read onlyDelete the node from the cluster # hagrp -delete grp4 Removing security credentials from the leaving node Modifying configuration files on each remaining node To determine the RPMs to remove, enter Stop GAB and LLT# /etc/init.d/gab stop # /etc/init.d/llt stop # rpm -qa grep Vrts # rm /etc/llttab # rm /etc/gabtab # rm /etc/llthosts Remove the LLT and GAB configuration files Creating a single-node cluster using the installer program About installing VCS on a single node Starting the installer for the single node cluster Preparing for a single node installationTasks to create a single-node cluster using the installer See Starting the software installation on Creating a single-node cluster manually Installing the VCS software manually on a single nodeSee Licensing VCS on Set the path variable Modifying the startup files Renaming the LLT and GAB startup filesVerifying single-node operation # hastart -onenode Adding a node to a single-node cluster Installing VxVM or VxFS if necessary Setting up a node to join the single-node cluster See Setting up shared storage on Configuring the shared storageDisplay the service groups currently configured Bringing up the existing node Freeze the service groups Configuring LLTStop VCS on Node a Rename the GAB and LLT startup files so they can be used Setting up /etc/llttab Setting up /etc/llthostsLLT directives See LLT directives on Directive Description Additional considerations for LLTLLT directives Reconfiguring VCS on the existing node Configuring GAB when adding a node to a single node clusterReconfigure VCS on the existing nodes Starting LLT and GAB Verifying configuration on both nodes Implement the new two-node configuration Unfreeze the service groupsStart the VCS on Node B Verify that VCS is up on both nodesPage See About adding and removing nodes on About the uninstallvcs programPreparing to uninstall VCS Removing VCS 5.0 RU3 RPMs Uninstalling VCS 5.0 RU3# cd /opt/VRTS/install # ./uninstallvcs Running uninstallvcs from the VCS 5.0 RU3 disc Uninstallvcs program is not available in /opt/VRTS/install When to use LLT over UDP Using the UDP layer for LLTConfiguring LLT over UDP Following checklist is to configure LLT over UDP See Sample configuration links crossing IP routers on Link command in the /etc/llttab fileBroadcast address in the /etc/llttab file See Broadcast address in the /etc/llttab file on Table A-2describes the fields of the set-addr command Set-addr command in the /etc/llttab file # setparms ipaddress Configuring the netmask for LLTSelecting UDP ports Sample configuration direct-attached links Configuring the broadcast address for LLTFor second network interface # cat /etc/llttab File for Node 1 resembles UDP Figure A-2 Sample configuration links crossing IP routers /etc/llttab file on Node 0 resembles Performing automated VCS installations Example response file Syntax in the response fileOr, in the case of an integer value Or, in the case of a list Table A-3 Response file variables Variable Description Response file variable definitions $CPICFGOPTLICENSE $CPICFGOPTPKGPATH $CPICFGKEYS Table A-3 $CPICFGOPTUNINSTALL See Installing and configuring VCS 5.0 RU3 on # ./installvcs -responsefile /tmp/installvcs-uui.response Index GAB RAM VCS