A Three HANA Node Example
In this example, two of the HANA nodes are ‘active’ and the third node is ‘standby’.
Active Server – host1
| /hana/log/DB1/mnt00001 | <- Mounts host1 Log_vDisk |
| /hana/data/DB1/mnt00001 | <- Mounts host1 Data_vDisk |
| /hana/log/DB1/mnt00002 | <- Mounts host2 Log_vDisk |
| /hana/data/DB1/mnt00002 | <- Mounts host2 Data_vDisk |
| /hana/shared | <- Mounts shared OCFS2 filesystem vDisk |
Active Server – host2
| /hana/log/DB1/mnt00001 | <- Mounts host1 Log_vDisk |
| /hana/data/DB1/mnt00001 | <- Mounts host1 Data_vDisk |
| /hana/log/DB1/mnt00002 | <- Mounts host2 Log_vDisk |
| /hana/data/DB1/mnt00002 | <- Mounts host2 Data_vDisk |
| /hana/shared | <- Mounts shared OCFS2 filesystem vDisk |
Active Server – host3 (in failover host role)
| /hana/log/DB1/mnt00001 | <- Mounts host1 Log_vDisk |
| /hana/data/DB1/mnt00001 | <- Mounts host1 Data_vDisk |
| /hana/log/DB1/mnt00002 | <- Mounts host2 Log_vDisk |
| /hana/data/DB1/mnt00002 | <- Mounts host2 Data_vDisk |
| /hana/shared | <- Mounts shared OCFS2 filesystem vDisk |
- Lines highlighted in blue are mounted when the database is started.
- Lines not highlighted are available (to that specific host) but are not mounted.
- In a ‘failover event’ the HANA application will determine which of the other hosts will mount and use the ‘failed host’s’ file systems.
- As any host at any time may require access to another other hosts’ file systems, all SANsymphony virtual disks used for ‘data’ or ‘log’ file systems must be served to all SAP HANA hosts all the time.