Managing Serviceguard Extension for SAP on Integrity Linux, December 2005

Understanding Serviceguard Extension for SAP on Integrity Linux
Networking
Chapter 118
Networking
Communication with the highly available components takes place by
using special IP addresses, called relocatable IP addresses. They are
handled by Serviceguard for Linux. Consider them as addresses of a
Serviceguard package rather than host machine addresses.
Some of the SAP processes still require that hostnames are not longer
than eight characters and do not contain special characters.
One additional IP address is the minimum address requirement for the
one package concept, two IP addresses are needed for the two package
solution (one for each package). If you are planning to use a frontend
LAN and a server LAN as suggested by SAP, double the number of IP
addresses, that is, use two or four.
You can reduce the number of additional IP addresses with the two
package concept if you do not want to access the database directly
through the frontend LAN. You can save another IP address, if you do not
have frontends that directly connect to the central instance, but only
access your SAP system through different application servers.
The reason for relocatable IP addresses on both networks is, that a
switchover must remain transparent to both the frontends and the
additional application servers.
The complete system is installed if there is no server LAN at all, that is,
all profiles only refer to addresses of the frontend LAN. Static routing of
the relocatable addresses from the client LAN to the server LAN redirect
the communication traffic of the application servers and the database to
the backend LAN.
For standard Network setup and the ability to use the bonding feature
for the network driver refer to the standard Serviceguard Linux manual.