SAP Note

Header Data

Symptom

You want to use SAP server software on Red Hat Enterprise Linux 6

Other Terms

Red Hat, Redhat, RH, Enterprise Linux, RHEL6, x86_64, ppc64, S390x

Reason and Prerequisites

You want to use SAP server software on Red Hat Enterprise Linux 6.x

Solution

Environment

This document deals with the installation and configuration of SAP server software on Red Hat Enterprise Linux 6. In the following, "RHEL 6" means any version of Red Hat Enterprise Linux 6.x unless specified otherwise. If RHEL 6 is listed as supported in the PAM this means that any update release of RHEL 6, for example RHEL 6 Update 1 (RHEL 6.1), can be used as well. The installation or configuration of Red Hat Enterprise Linux as the base of a database server is not the primary purpose of this document although some notes listed below are specific to the database you want to run with SAP. If you want to install a database server, consult the operating system and database system documentation as well.

Supportability prerequisites

In order for your SAP system to be fully supported on Red Hat Enterprise Linux 6, the following prerequisites must be fulfilled (this list is not exclusive, other notes may apply):

l You need to use the RHEL 6 server variant.

l You need to have valid support and update entitlements ("subscriptions") from Red Hat for Red Hat Enterprise Linux 6 and any additional layered components (e.g. Virtualization, Clustering, Cluster Storage).

Red Hat recommendsto get "RHEL for SAP Business Applications" subscriptions for all RHEL6 servers running SAP applications. See SAP note 1631106 or go to http://www.redhat.com/products/enterprise-linux/for-sap/ for more information. Please contact your local Red Hat sales representative to purchase RHEL subscriptions.

l Your machine must be able to retrieve additional software and updates from "Red Hat Network" (RHN) either directly via HTTP or an RHN proxy or through a RHN Satellite server.

l You need to use hardware that is certified for SAP use on Linux by your hardware vendor. See the respective notes on certified hardware which are listed in SAP note 171356.

l You can use any Linux kernel version shipped by Red Hat for Red Hat Enterprise Linux 6

l You can use any glibc version shipped by Red Hat for Red Hat Enterprise Linux 6

l It is recommended to always install the latest available patches and quaterly updates.

l If you plan to run SAP Java-based applications you need a fully supported Java stack. For SAP releases for which the usage of the SAPJVM is not yet supported (see SAP note 1495160) you should get a supported version of the JDK for your hardware platform. Please see SAP notes 1172419 (x86_64), 1408282 (IBM Power) and 1465174 (IBM System Z) for more information on how to obtain a vendor supported JDK.

Supported Hardware Platforms

Certification of specific SAP products on specific versions of Red Hat Enterprise Linux notwithstanding, the following hardware platforms are certified for use of SAP software on Red Hat Enterprise Linux:

l x86_64 (64bit Intel or AMD processors)

l IBM P-Series (PPC64)

l IBM System Z (S390x)

1496410 - Red Hat Enterprise Linux 6.x: Installation and Upgrade

Version 24 Validity: 19.09.2013 - active Language Ingls

Released On 19.09.2013 17:28:55 Release Status Released for Customer Component BC-OP-LNX-RH Red Hat Linux Priority Recommendations / Additional Info Category Installation information

Please note that Red Hat Enterprise Linux 6 does not support the Intel Itanium platform.

Upgrading from a previous Red Hat Enterprise Linux release to RHEL 6

Red Hat does not support in-place upgrades from one major RHEL release (e.g. RHEL 5) to RHEL6 (see https://access.redhat.com/knowledge/solutions/21964). The only supported option to upgrade from an older RHEL release to RHEL 6 is to backup all data on the system, install and configure RHEL 6 on the server and then reinstall the applications and restore the data from backup.

Installing Red Hat Enterprise Linux

Install the operating system as described in its documentation ("Red Hat Installation Guide", either the handbook or from installation media). Install the minimum operating system components mentioned below. Use English as the installation and system language. Note that some things that were configured during the installation in former versions of RHEL are now configured during the first boot after installation. Additional notes:

l Manually partitioning the disks is strongly recommended to reserve space for the application.

l When asked about the desired timezone, select the correct timezone and choose"System clock uses UTC"in order to automatically switch between normal and daylight savings time.

l When prompred for the hostname, enter the short name (e. g. "sapserver1") and not the fully qualified hostname (e. g. "sapserver1.example.com"). How to map the short hostname to the fully qualified hostname is described below under "Hostname".

l When asked to customize the software selection, choose "Basic Server" and then select the "Customize now" option. It is recommended to select the software groups listed in the following at a minimum for an SAP server machine. When customizing the list of optional packages for a software group, keep the packages selected by default and add packages eventually listed with the group. This is the list of categories/groups that should be selected during installation:

Base System

Base Compatibiliy Libraries Debugging Tools Directory Client Hardware Monitoring Utilities Large Systems Performance Network File System client Perl support Storage Availability Tools

Desktops

X window system

Development

Development tools (only required when installing SAP with Oracle DB) Please make sure that the following packages are always included in the list of packages selected for installation:

uuidd (see SAP note 1391070)

If you plan to use Adobe Document Services, some additional packages have to be installed. Please see SAP note 1633459 for more information. Please see the section "Installing additional software packages" below for instructions on how to install additional packages after the OS installation.

Configuration steps necessary after the initial OS installation Firstboot

When you first boot your system you will be presented with "firstboot", a post installation configuration tool:

l If you leave the firewall enabled, you need to open up the ports for your SAP product either in firstboot if you already know them or by e.g. using the system-config-firewall tool at a later point. These ports are listed during the installation of the SAP software but can also be found in /etc/services after it is installed.

l Red Hat Enterprise Linux uses SELinux technology for additional security which is enabled by default. Because several components of an SAP server system (like the installation tools or some underlying RDBMS) are not aware of SELinux, we recommend setting it to "Permissive" for the time being so that these components won't break. We don't recommend setting it to "Disabled" as this would require relabeling the whole filesystem if you want to enable it again at a later point for additional security when these components are made compatible or suitable procedures exist to make them function properly with SELinux. You can change SELinux settings by editing /etc/sysconfig/selinux for future boot processes. On a running system, you can switch between "Enforcing" and "Permissive" modes using the command "setenforce".

l If you can access an NTP time server from the machine, we strongly recommend choosing "Enable Network Time Protocol" in the "Date and Time" dialog to keep all SAP applications servers' time and date synchronized.

l You have to register the system in the Red Hat Network (RHN) to retrieve update packages for your machine. It is recommended that you update all program packages (including kernel and glibc) to the latest version available on RHN after the first OS installation and at regular intervalls later on.

Hostname

Ensure that the system hostname is set to the short name as described above, i.e. both commands "hostname" and "hostname -s" must return the hostname without domain, "hostname -f" must return the fully qualified hostname and domain: # hostname sapserver1 # hostname -s sapserver1 # hostname -f sapserver1.example.com To do that, check that HOSTNAME is set to the short name without domain in /etc/sysconfig/network: # cat /etc/sysconfig/network NETWORKING=yes HOSTNAME=sapserver1 ... Also set up /etc/hosts so that it is configured similar to the following example: # cat /etc/hosts 127.0.0.1 localhost.localdomain localhost 192.168.0.1 sapserver1.example.com sapserver1 (any additional hosts should be added after these two lines)

It is important that the fully qualified domain name is in the second column, followed by any alias names and that the hostname of the machine is not associated with the IP address 127.0.0.1. If you entered the fully qualified hostname during installation you can run the command 'hostname ' to set the short hostname without having to reboot the system.

Linux kernel parameters

Some Linux kernel parameters have to be adjusted to meet the requirements of SAP software. To do this append the following lines to /etc/sysctl.conf, or change the already existing parameters accordingly (these are the required minimum values, higher values are okay as well): # SAP settings kernel.msgmni=1024 kernel.sem=1250 256000 100 1024 vm.max_map_count=2000000 (see SAP Note 900929 for more information) Please check SAP note 941735 for recommendations on how to configure the kernel parameters kernel.shmmax and kernel.shmall and other memory related settings for 64bit systems. Run the command "sysctl -p" to activate the modified kernel parameters.

Process resource limits

Some components (e.g. the SAP J2EE engine, Oracle RDBMS software, ...) need to keep a large number of file handles opened simultaneously. You need to increase the limit of files one process can open at a time by extending /etc/security/limits.conf with the following lines: @sapsyshardnofile32800 @sapsyssoftnofile32800 @dba hardnofile32800 @dba softnofile32800 Please logout and login again for these settingss to take effect. With these settings the users in the sapsys group (J2EE engine) and the dba group (Oracle) can open up to 32800 files simultaneously. If needed, adjust these lines to match your setup. Please refer to the comments in said file for information about its format. By default RHEL 6 limits the number of simultaneous processes for each user to 1024 to prevent so called "fork-bomb" attacks. This can cause problems when running multiple SAP JAVA app server instances under the same userid. If you plan to run such a setup on RHEL6, please also add the following line in /etc/security/limits.conf: @sapsyssoftnprocunlimited To ensure that the process resource limits also get adjusted when the SAP system is started via sapcontrol or a web service client (e. g. SAP MMC) please make sure to adjust the limits in the file /usr/sap/sapservices as described in SAP note 1437105. You can determine if your system is under control of sapcontrol by checking if its start command is contained in /usr/sap/sapservices.

Installing additional software packages

You can also install or reinstall a package or a package group at a later point (after registering your system in "Red Hat Network" (RHN)) with the following commands, provided that your system can access RHN via the officially supported ways (directly or via RHN Proxy or RHN Satellite):

l For installing individual packages:

yum install [ [< package3> [...]]] where are the names of the packages to be installed, e.g.: yum install uuidd

l For installing package groups:

yum groupinstall '' ['' ['< group3' [...]]] where are the names of the groups you want to install. The following yum groups correspond to the groups listed for the installation program above: base compat-libraries debugging directory-client hardware-monitoring large-systems network-file-system-client perl-runtime storage-client-multipath x11 development (only required when installing SAP with Oracle DB) If your system can't use the officially supported ways to access "Red Hat Network" (RHN), it often means "yum" cannot determine the individual packages contained in a package group. In this case, you need to install the individual packages as described above. To find out which packages fulfill a certain requirement or are part of a certain package group, please contact your operating system support.

Threading on Red Hat Enterprise Linux 6.x

Red Hat Enterprise Linux 6.x uses the Native Posix Threading Library, a POSIX-compatible threading implementation, for threading. Unlike former versions of RHEL, using LinuxThreads for older applications by way of setting the environment variable LD_ASSUME_KERNEL to 2.4.1 doesn't work anymore and will probably prevent most programs from being run at all if it is set.

Red Hat supported IBM 1.4.2 JDK for x86_64

To install the Red Hat supported IBM 1.4.2 JDK as listed in SAP note 1172419, please make sure that the system is subscribed to the "RHEL for SAP" channel on RHN or your local RHN Satellite. If the system is subscribed correctly you should see the following in the output of the "yum repolist" command: rhel-x86_64-server-sap-6 RHEL for SAP (v. 6 for 64-bit x86_64) You can then install the required IBM 1.4.2 JDK packages via the following commands: yum install java-1.4.2-ibm-sap yum install java-1.4.2-ibm-sap-devel To avoid that the IBM 1.4.2 JDK packages get overwritten during a update you should add the following line to /etc/yum.conf: exclude=java-1.4.2-ibm-sap* If you plan to run SAP Java-based applications on Sybase ASE 15.7, no additional JDK is required as the SAPJVM is part of the installation media.

Minimum SAP patchlevels

Some installation media contain old patchlevels of the SAP software. For proper functioning of your SAP system, ensure that you have installed at minimum the patchlevels listed here: SAP kernel 6.40: patchlevel >= 12

Patching SAPINST

In some cases SAPINST will fail during start or terminate abnormally and needs to be patched. Please refer to and proceed according to note

722890 for information about where to download SAPINST patches and how to apply them.

Additional notes for installing SAP systems

l You may get a warning from the Prerequisite Checker that Red Hat Enterprise Linux 6.x is not supported. Ignore this warning.

l When installing an SAP system based on kernel 640, you need to update the SAP kernel to a current patchlevel, then continue with the installation of the DB instance, see SAP note 19466 for details. In the DB installation, when asked whether you want to extract the SAP kernel SAPEXE and SAPEXEDB archives, uncheck these options so that the updated kernel files don't get overwritten with old versions.

l When using SAP software in an LDAP environment on RHEL 6/x86_64, you need to install a symbolic link for two libraries because the SAP binaries used to access LDAP where built against versions of these libraries with a non-standard SONAME:

ln -s /usr/lib64/libldap-2.3.so.0 /usr/lib64/libldap.so.199 ln -s /usr/lib64/liblber-2.3.so.0 /usr/lib64/liblber.so.199 For this to work you need to have the compat-openldap package installed.

l When using R3SETUP to install older product releases, you might encounter an error looking like this:

[...] error while loading shared libraries: libstdc++-libc6. 1-1.so.2: cannot open shared object file: No such file or directory In this case, run the following command as the root user to create a symlink to the newer version of the library: ln -s /usr/lib/libstdc++-libc6.2-2.so. 3 /usr/lib/libstdc++-libc6.1-1.so.2 Please make sure the the compat-libstdc++-296 package for i686 is installed to make this work.

Backup

When using BRBACKUP, don't use the cpio tool as a backend because it can't restore archives larger than 4GB. See SAP note 20577 for details.

Known Issues

l RHEL6.0, RHEL6.1 or RHEL6.2 systems might reboot with sched_clock() overflow after an uptime of around 208.5 days

Solution: For critical production systems that cannot update their kernel version, we currently recommend a cold reboot before the system reaches 208 days uptime. A fix for this issue has been released with kernel-2.6.32-279. el6. If possible, please update your system to this or a later version of the RHEL6 kernel. For further information please see: https://access.redhat. com/site/solutions/68466

l You may encounter problems during an installation of SAP NetWeaver when using Hummingbird Exceed version 10.0.0.0 or lower. After starting the SAP installer "sapinst", the installation window will not appear, however the installation process will not terminate.

Solution: Upgrade to Exceed to version 10.0.0.15 or later.

Additional notes for installation with SAP MaxDB

l At least MaxDB 7.7 is required.

Additional notes for installation with Sybase ASE

l At least Sybase ASE 15.7 is required.

l Some additional kernel parameters have to be adjusted for Sybase ASE to work on RHEL 6:

kernel. randomize_va_space=0 kernel. exec-shield=0 Please add those two lines to /etc/sysctl. conf and activate the new settings with "sysctl -p". (see SAP Note 1570335 for more information)

Additional notes for installation with IBM DB2 for LUW on Linux x86_64 and Linux on Power Systems

l At least IBM DB2 9.5.0.7 for LUW or IBM DB2 for LUW 9.7.0.4 is required.

Additional notes for installation with Oracle

l At least Oracle 11.2.0.3 is required.

l For the Oracle installer to work, you also need to have the following packages installed (the installer might still complain due to the versions of the packages, but you can ignore this error):

libaio

libaio-devel

compat-libstdc++-33

elfutils-libelf-devel

libgcc

libstdc++

unixODBC

unixODBC-devel

ksh or mksh

l Please make sure to follow the Oracle installer recommendations for setting additional kernel parameters during the installation.

l It is highly recommended to configure Oracle to use hugepages on RHEL6. Please see SAP note 1672954 for more information.

l Please check SAP note 1642058 for instructions on how to install the required Oracle Instant Client 11.2.0.3.

Validity

This document is not restricted to a software component or software component version

References

This document refers to:

SAP Notes

This document is referenced by:

SAP Notes (20)

1172419 Linux: Supported Java versions on the x86_64 platform 1379130 Linux: Released NEC hardware 1391070 Linux UUID solutions 1400911 Linux: SAP on Red Hat KVM - Kernel-based Virtual Machine 1403020 Linux: Certified Cisco Hardware 1431800 Oracle 11.2.0: Central Technical Note 1437105 Operating system limits for SAP instances 1452070 DB2-z/OS: SAP on Linux for IBM System z and z/VM 1631106 Red Hat Enterprise Linux for SAP Business Applications 1633459 Required RPM package for ADS on RHEL 6 and Oracle Linux 6 1642058 Adapt SAPInst Oracle Client 11.2.0.x 1642936 Support for SAP software in RHEL with MC support of NEC 1644499 Database connectivity from Linux to SQL Server 1672954 Oracle 11g: Usage of hugepages on Linux 1678024 Linux: NetWeaver 7.0 EhP 3 with SAP kernel 720

171356 SAP software on Linux: Essential information 1769251 Incorrect CPU metrics on RHEL 6.3 on IBM POWER 1908655 Support details for Red Hat Enterprise Linux HA Add-On

900929 Linux: STORAGE_PARAMETERS_WRONG_SET and "mmap() failed" 936887 End of maintenance for Linux distributions

171356 SAP software on Linux: Essential information 936887 End of maintenance for Linux distributions 1452070 DB2-z/OS: SAP on Linux for IBM System z and z/VM 1631106 Red Hat Enterprise Linux for SAP Business Applications 1633459 Required RPM package for ADS on RHEL 6 and Oracle Linux 6 1642058 Adapt SAPInst Oracle Client 11.2.0.x 1642936 Support for SAP software in RHEL with MC support of NEC 1644499 Database connectivity from Linux to SQL Server 1391070 Linux UUID solutions 1769251 Incorrect CPU metrics on RHEL 6.3 on IBM POWER 1400911 Linux: SAP on Red Hat KVM - Kernel-based Virtual Machine 1403020 Linux: Certified Cisco Hardware 900929 Linux: STORAGE_PARAMETERS_WRONG_SET and "mmap() failed" 1908655 Support details for Red Hat Enterprise Linux HA Add-On 1672954 Oracle 11g: Usage of hugepages on Linux 1678024 Linux: NetWeaver 7.0 EhP 3 with SAP kernel 720 1431800 Oracle 11.2.0: Central Technical Note 1437105 Operating system limits for SAP instances 1172419 Linux: Supported Java versions on the x86_64 platform 1379130 Linux: Released NEC hardware