Virtual host names are based on domain name server (DNS) entries resolved to virtual internet provider addresses (VIPs). VIPs can be bonded to any network interface. You can perform matching forward and reverse virtual IP DNS lookups.
A forward VIP DNS lookup enables you to use a known domain name during a name query and looks up the IP address based on the domain name. For this process, the DNS requires A (address) records. You cannot use CNAME records.
A reverse VIP DNS lookup enables you to use a known IP address during a name query and looks up the domain name based on the IP address.
To set up virtual host names you need the following:
To change an existing setup the system copy is the only officially supported way to change a productive system. This is done using the Software Provisioning Manager (
The figure, The Adaptive Design - Relocate in Detail, shows an example landscape consisting of SAP ERP, SAP CRM, and an additional application server, D01 of SAP ERP. They all have their own virtual host names and their own storage volumes.
The figure The Adaptive Design - Relocate in Detail II shows how D01 will be stopped.
The figure The Adaptive Design - Relocate in Detail III shows how D01 will be unprepared. This means the unbinding of the virtual host name from the Network Interface Card (NIC) and unmounting the file systems configured.
The figure The Adaptive Design - Relocate in Detail IV shows how D01 will be prepared on target host (host02 in the figure). This means binding the virtual IP addresses to the NIC and mounting the file systems configured.
The figure The Adaptive Design - Relocate in Detail V shows how D01 is started on host02.
The figure The Adaptive Design - Types of Relocate shows the different types of relocates:
P2P = Physical-to-Physical.
P2V = Physical-to-Virtual.
V2P = Virtual-to-Physical.
V2V = Virtual-to-Virtual (i.e. relocate from VM to another VM, not the same as "migrate").
The figure, The Difference to Virtual Machines - VM-Migration (V2V), shows the difference in virtual machines (VMs).
VM-migration is a generic term to describe a hypervisor based movement of a VM. Each hypervisor vendor has their own naming such as VMware Vmotion, IBM Partition Mobility, Hyper-V live migration. A VM-migration should not be confused with an SAP System (OS/DB) migration or an Adaptive Design Relocate.
The figure The Difference to Virtual Machines - VM-Migration (V2V) II shows how D01 is migrated to a different host. SAP Landscape Management triggers the virtualization manager via a so called adapter to migrate the system to a different VM host.
The figure, The Difference to Virtual Machines - VM-Migration (V2V) III, shows the difference in VMs.
The adaptive design concept relies on shared connectivity to storage devices and makes file systems visible on different hosts within the landscape.
SAP Landscape Management can be integrated with Network Attached Storage (NAS) technologies that can be shared on multiple hosts at the same time, and Storage Area Networks (SAN) technologies that can be attached to only one host at a given point in time.
It is important to understand the differences between NAS and SAN when designing and configuring an adaptive or SAP Landscape Management managed SAP landscape.
There are two possible ways of setting up your SAP system database, depending on your OS and database:
Your database software runs together with your database files and is adaptively installed as a whole unit.
Your database files are adaptive and enabled and SAP Landscape Management moves your database around. In this case, you need to ensure that the software is installed on all eligible hosts.
Understanding NAS — File Based Storage
- NAS Technology
- NAS and hypervisors
- Network based communication makes the integration with VMs easier.
- NAS Connections
- Key Properties of NAS
- Enables exported volumes to be simultaneously mounted on multiple hosts to provide shared access to the same file system which can dramatically simplify the configuration of an adaptive design.
The figure, NAS, shows how NAS provides so called NFS exports, which are directly mountable.
The figure Mount Point Setup — NFS Example shows an example of a mount point setup for NFS. Row L (gray) shows the local mount point. For mount points you must always distinguish between the local part and the mounted part.
Typically, a database spans multiple storage volumes.
/sybase/<SID> is just a placeholder. Even though it is possible to share the complete
/usr/sap/<SID> mount point between hosts, it is recommended to use separate mount points for all instances, for example
/usr/sap/<SID>/<instance name>, to avoid potential conflicts.
Understanding SAN — Block Based Storage
- SAN technology
- Is about simple block devices made visible to the OS.
- SAN and Hypervisors
The connectivity of fiber channel devices into VMs can require extra configuration, for example, VMWare Raw Device Mapping.
The integration of block storage with hypervisors is handled transparently by several SAP Landscape Management storage integrations.
- SAN Connectivity Options
- Block Devices
- Key Properties of SAN
Landscapes do not share file systems simultaneously between hosts in general.
Non-shared file systems have a significant impact on the adaptive design.
Landscapes usually require at least some shared access file systems (for example, NAS or NFS) for directories such as
Please notice the difference between SAN (non-shared file systems) and NFS (shared file systems). Even in the SAN environment some directories need to be shared between instances. This can be accomplished using NFS shares. Selected instances (such as Central Services and Dialog Instance) were selected as examples. Instance directories might be different according to your system setup. Instances may not span storage volumes or volume groups (if used). Symbolic links can be used but require extra maintenance. Typically, a database would span multiple storage volumes.
/sybase/<SID> is just a placeholder.
You can manage OS and DB users and groups in a central identity management system, for instance in an adaptively enabled landscape (for example, Lightweight Directory Access Protocol [LDAP] or Active Directory).
If you do not use a central identity management system, ensure that OS and DB users and groups are consistently available on the OS.
Central identity management is preferred as it makes it much more comfortable and easier to handle the user management.
SAP NetWeaver for SAP Landscape Management provides the following main integration points for SAP Partner Technologies:
- Virtualization and Cloud
Integration into a VM or Cloud management infrastructure.
Manage, migrate, visualize, and perform a VM-based clone.
The integration of SAP Partner Technologies is handled via so-called adapters provided by our partners.
SAP Landscape Management can integrate partner solutions for example to trigger a clone of a VM or cloning of storage volumes.