1. Determine which configuration you wish to use. The required tasks vary depending on the configuration.
  1. Determine whether the SAP system-wide /usr/sap/trans directory will be hosted on the SAP Primary Application Server or on a file server. It can be hosted either place as long as it is NFS shared and fully accessible. If it is hosted on the SAP Primary Application Server and located on a shared file system, it should be protected by LifeKeeper and included in the SAP hierarchy.
  1. Consider the storage requirements for SAP and DB as listed in the SAP Installation Guide. Most of the SAP files will have to be installed on shared storage. Consult the SPS for Linux Technical Documentation for the database-specific recovery kit for information on which database files are installed on shared storage and which are installed locally. Note that in an SAP environment, SAP requires local access to the database binaries, so they will have to be installed locally. Determine how to best use your shared storage to meet these requirements.

Also note that when shared storage resources are under LifeKeeper protection, they can only be accessed by one server at a time. If the shared device is a disk array, an entire LUN is protected. If a shared device is a disk, then the entire disk is protected. All file systems located on a single volume will therefore be controlled by LifeKeeper together. This means that you must have at least two logical volumes (LUNs), one for the database and one for SAP.

  1. Virtual host names will be needed in order to identify your systems for failover. A new IP address is required for each virtual host name used. Make sure that the virtual host name can be correctly resolved in your Domain Name System (DNS) setup, then proceed as follows:

a. Create the new virtual ip addresses by using the command:

ip {IPADDRESS}/{NETMASK} dev eth0 (use the right netmask for your configuration)

Note: To verify these new virtual ip addresses use the ip addr show command.

b. A separate virtual IP will also be needed for the ERS instance if using ERSv2.

In order to associate the switchable IP addresses with the virtual server name, edit /etc/hosts and add the new virtual ip addresses.

Note: This step is optional if the Primary Application Server and the Database are always running on the same server and communication between them is always local. But it is advisable to have separate switchable IP addresses and virtual server names for the Primary Application Server and the Database in case you ever want to run them on different servers.

  1. Stop the caching daemon on both machines.

rcnscd stop

  1. Mount the software.

mount //{path of software} (no password needed)

  1. Run an X session (either an ssh -X or a VNC session — for Microsoft Windows users, Hummingbird Exceed X Windows can be used).

Note: When sapinst is run, the directory will be extracted under /tmp

  1. When installing SAP (specifically ASCS or SCS) you need to specify the SAPINST_USE_HOSTNAME=vip option. This is also required for the ERS instance if using ERSv2, but not if using ERSv1.

Note: Specify sapinst SAPINST_USE_HOSTNAME=vip where vip is the virtual IP that will float between the nodes.

Important Note

The LifeKeeper SAP Recovery Kit relies on the SAP Host agent being installed. If this software is not installed, then the LifeKeeper SAP kit will not install. With SAP Netweaver Version 7.3 and higher, this host agent is supplied; however, prior versions require a download from SAP. It is recommended that you consult your SAP help notes for your specific version. You can also refer to the Help Forum (help.sap.com) for further documentation.

  • The saphostexec module, either in RPM or SAR format, can be downloaded from SAP.
  • To make sure that the modules are installed properly, there are a few modules to search for (saposcol, saphostexec, saphostctrl). These modules are typically found where SAP is installed (typically /usr/sap directory).

Feedback

Was this helpful?

Yes No
You indicated this topic was not helpful to you ...
Could you please leave a comment telling us why? Thank you!
Thanks for your feedback.

Post your comment on this topic.

Post Comment