Red Hat CLUSTER SUITE FOR ENTERPRISE LINUX 5.2 Guida di Installazione

1.5 SAP OverviewIn an SAP NetWeaver environment, these single points of failure (SPOF) must be considered: Database SAP Central Services Instance (

To ensure that the (A)SCS "follows" the ERS instance, the follow-service dependency wasimplemented in RHCS.The SAP System Mount Directory sh

 Cluster Servers: (2) Fujitsu Siemens Rx220 Storage: EMC CLARiiON SAN Infrastructure: QLogicSAP Installation: SAP NetWeaver 2004, WebAS ABAP on

3.3 Network RequirementsThere should be at least two Network Interface Cards (NIC), whether embedded or added toeach server. Where multiple network i

In the event of a major network problem, cluster partitioning (aka: split-brain situation) canoccur. Each partition can no longer communicate with nod

The quorum disk daemon (qdiskd) runs on each node in the cluster, periodically evaluating itsown health and then placing its state information into an

GFS runs on each node in a cluster. As with all file systems, it is basically a kernel modulethat runs on top of the Virtual File System (VFS) layer o

Please note, that the SCSI fencing mechanism requires persistent SCSI reservations. Pleasecontact Red Hat technical support and your storage hardware

On a clustered volume group, the following command can be used to create a cluster awaremirror:# lvcreate -m1 -L 1G -n my_new_lv my_vg 4.10 Cluster Re

Compared to other cluster concepts, the management and operation is straightforward. Withclassic application clusters, the complexity of management is

Deploying Highly Available SAP® Servers using Red Hat® Cluster Suite1801 Varsity DriveRaleigh NC 27606-2072 USAPhone: +1 919 754 3700Phone: 888 733 4

fence device, disable ACPI Soft-Off for that node. Otherwise, if ACPI Soft-Off is enabled, anintegrated fence device can take four or more seconds to

5.2.3 Hosts fileThe /etc/hosts file for each cluster member should contain an entry defining localhost. If theexternal host name of the system is def

5.3.3.1 LVM ConfigurationThe LVM configuration file /etc/lvm/lvm.conf must be modified to enable the use of CLVM.1. By default, the LVM commands scan

mechanism In a cluster setup, lockproto:=lock_dlmFurther information about the gfs_mkfs option can be obtained from the gfs:mkfs(8) manpage.The follow

gpgkey=http://download.atix.de/yum/comoonics/comoonics-RPM-GPG.keyInstall the required open-sharedroot software packages:# yum install comoonics-booti

2. Update the ccs cluster configuration:# ccs_tool update /etc/cluster/cluster.confThe <cluster> tag should define the following attributes:Attr

Attribute Descriptionto CMAN when it has a high enough score. log_level Controls the verbosity of the quorum daemon in thesystem logs. 0 = emergenc

For more detailed information, refer to the qdisk man page.If device mapper multipath is used together with qdiskd, the values for tko and interval mu

fencing mechanism are encapsulated within the <fence> tag. Each fencing mechanism isdefined by the <method> tag.Please refer to the man pa

After the installation of the first node is complete, the installation must be transferred to ashared root device and some modifications must be perfo

Table of Contents 1 Executive Summary...7

6.1.2 SAP Virtual IP AddressesSAP NetWeaver is typically installed via the graphical installation tool sapinst. Beforebeginning the installation, det

Follow the database file system configuration recommendations from the SAP installationguide. It is recommended to have physically different mount poi

Depending on the Installation Master CD that was used for the SAP installation, the loginprofiles for the SAP administrator user (<sid>adm) and

As a general requirement, the SAP parameter es/implementation must be set to "std" in theSAP DEFAULT.PFL file. See SAP Note 941735. The SAP

6.2.2 SAP Virtual IP AddressesSAP NetWeaver is typically installed via the graphical installation tool sapinst. Beforebeginning the installation, det

The transport directory /usr/sap/trans should also be exported via NFS according to your SAPlandscape. 6.2.3.4 Before Starting the SAP InstallationBef

Copy the files /etc/oratab and /etc/oraInst.loc to the GFS mount point /oracle and create linksto them. 6.2.5.3 SAP ProfilesThe most important SAP pro

6.3 Shared Root and Shared Storage with GFS 6.3.1 SAP ArchitectureFollowing the established SAP documentation is highly recommended: SAP Installatio

The database directories can also completely reside on GFS. Follow the database file systemsetup recommendations from the SAP installation guide. It i

6.3.5.2 SAP ProfilesThe most important SAP profile parameter for a clustered SAP system is SAPLOCALHOST.After the installation with sapinst, ensure t

5.1.2 ACPI...19 5.1.3 Firewall...

The following resource types will be defined to provide the high availability functionality forSAP. 7.2 ConfigurationThe resource group manager is con

basic configuration schema:<rm> <failoverdomains> <failoverdomain name="name" restricted="[0|1]" ordered=&quo

7.4 Cluster Resources and ServicesThere are many types of cluster resources that can be configured. Resources are bundledtogether to highly available

7.4.1 IPThe ip resource defines an ipv4 or ipv6 network address. The following attributes can bedefined:Attribute Description Requiredaddress IPv4 or

Attribute Description Requiredreferencemountpoint Path within file system hierarchy at which tomount this file system.Yesdevice Block device, file sys

standalone web dispatcher instance which will fail to work with the resource agent. The nextversion of the agent can have a parameter that could be us

Attribute Description Requiredafter the default SAP installation. DEFAULT:/usr/sap/<SID>/<INSTANCE>/exeor /usr/sap/<SID>/SYS/exe/run

Attribute Description Requiredbe more important that the ABAPinstance be up and running. A failure ofthe JAVA instance will not cause afailover of the

Attribute Description RequiredPOST_STOP_USEREXIT uses. Those programs can include bywriting an OCF resource agent into theHeartbeat cluster. However,

Attribute Description RequiredDIR_EXECUTABLE The full qualified path to the SAP kernel.The resource agent requires the startdband the R3trans executab

6.1.5.4 SAP Release-specific Post-processing...33 6.1.5.5 Before Starting the Cluster...

Attribute Description RequiredNot fort use with Oracle as it will result inunwanted failovers in the case of a stuckarchiver. DEFAULT: falseAUTOMATIC_

Attribute Description RequiredThis is required only if theDBJ2EE_ONLY parameter is set to true. It will be automatically read from thebootstrap.proper

7.5 Dependencies 7.5.1 Resource DependenciesThe resources within a cluster service follow two different dependency rules. First, the nesting within t

7.5.2.2 Follow Service DependencyThe follow service dependency makes use of rgmanager's RIND event scripting mechanism.In order to activate the

8 Cluster Management 8.1 CMANThe basic cluster operation can be verified using the cman_tool utility 8.1.1 cman_tool statusThe cman_tool status comma

dlm 1 root 00040001 none [1 2] dlm 1 clvmd 00020001 none [1] dlm 1 rhc_a

8.2.2 clusvcadmThe resource manager services can be controlled by the clusvcadm command. The basicoperations are: clusvcadm -e <service> -m &l

8.3.2 Update initrdIn a sharedroot cluster, the cluster configuration file /etc/cluster/cluster.conf must be copiedinto the initrd. Therefore the pro

enterprisecopy/localclone.xmlFor detailed information regarding the comoonics enterprise software solution, please consultthe Comoonics Enterprise Cop

</clusternodes> <fencedevices> <fencedevice name="ipmi" agent="fence_ipmilan" auth="password"logi

7.4.3 FS...44 7.4.4 SAPInstance

evalfile("/usr/local/cluster/follow-service.sl"); follow_service("service:rhc_ascs", "service:rhc_ers",&

## Device attributes for EMC CLARiiON device { vendor "DGC " product "*" getuid_call

multipath { wwid 360060160eda50800a155ad9b6a54db11 alias DGC_012 } multipath { wwid 360060160eda508009f55ad9b6a54db11 alias DGC_013 } mult

scan = [ "/dev/mapper" ] # If several entries in the scanned directories correspond to the # same block device and the tools nee

# It is safe to delete the contents: the tools regenerate it. # (The old setting 'cache' is still respected if neither of # thes

# What level of log messages should we send to the log file and/orsyslog? # There are 6 syslog-like log levels currently in use - 2 to 7inclus

archive_dir = "/etc/lvm/archive" # What is the minimum number of archive files you wish to keep ? retain_min = 10 # What

"lvm2". # The command line override is -M1 or -M2. # Defaults to "lvm1" if compiled in, else "lvm2". # forma

# For now, you need to set this up yourself first (e.g., with'dmsetup') # For example, you could make it return I/O errors using the

# Currently this is not implemented properly and behaves # similarly to: # # "allocate_anywhere" - Ope

1 Executive SummaryThis paper details the deployment of a highly available SAP service on a Red Hat EnterpriseLinux 5 cluster. After an introduction

# Event daemon # # dmeventd { # mirror_library is the library used when monitoring a mirror device. # # "libdevmapper-event-lvm2mirro

1.2 AudienceThis document addresses SAP certified technical consultants for SAP NetWeaver withexperience in HA systems. Access to SAP information res

RHCS Red Hat Cluster SuiteRHEL Red Hat Enterprise LinuxRIND Rind Is Not DependenciesSAN Storage Area NetworkSCS SAP Central Services Instance (for J