Adding additional data volume partitions for SAP HANA single-host systems
Starting with SAP HANA 2.0 SPS4, additional data volume partitions can be configured. This feature allows you to configure two or more LUNs for the data volume of an SAP HANA tenant database and to scale beyond the size and performance limits of a single LUN.
It is not necessary to use multiple partitions to fulfill the SAP HANA KPIs. A single LUN with a single partition fulfills the required KPIs. |
Using two or more individual LUNs for the data volume is only available for SAP HANA single-host systems. The SAP storage connector required for SAP HANA multiple-host systems does only support one device for the data volume. |
Adding additional data volume partitions can be done at any time but might require a restart of the SAP HANA database.
Enabling additional data volume partitions
To enable additional data volume partitions, complete the following steps:
-
Add the following entry within the
global.ini
file.[customizable_functionalities] persistence_datavolume_partition_multipath = true
-
Restart the database to enable the feature. Adding the parameter through the SAP HANA Studio to the
global.ini
file by using the Systemdb configuration prevents the restart of the database.
Volume and LUN configuration
The layout of volumes and LUNs is like the layout of a single host with one data volume partition, but with an additional data volume and LUN stored on a different aggregate as the log volume and the other data volume. The following table shows an example configuration of an SAP HANA single-host systems with two data volume partitions.
Aggregate 1 at Controller A | Aggregate 2 at Controller A | Aggregate 1 at Controller B | Aggregate 2 at Controller B |
---|---|---|---|
Data volume: SID_data_mnt00001 |
Shared volume: SID_shared |
Data volume: SID_data2_mnt00001 |
Log volume: SID_log_mnt00001 |
The following table shows an example of the mount point configuration for a single-host system with two data volume partitions.
LUN | Mount point at HANA host | Note |
---|---|---|
SID_data_mnt00001 |
/hana/data/SID/mnt00001 |
Mounted using /etc/fstab entry |
SID_data2_mnt00001 |
/hana/data2/SID/mnt00001 |
Mounted using /etc/fstab entry |
SID_log_mnt00001 |
/hana/log/SID/mnt00001 |
Mounted using /etc/fstab entry |
SID_shared |
/hana/shared/SID |
Mounted using /etc/fstab entry |
Create the new data LUNs using either ONTAP System Manager or the ONTAP CLI.
Host configuration
To configure a host, complete the following steps:
-
Configure multipathing for the additional LUNs, as described in chapter 0.
-
Create the XFS file system on each additional LUN belonging to the HANA system:
stlrx300s8-6:/ # mkfs.xfs /dev/mapper/hana-SS3_data2_mnt00001
-
Add the additional file system/s to the
/etc/fstab
configuration file.The XFS file systems for the data and log LUN must be mounted with the relatime
andinode64
mount options.stlrx300s8-6:/ # cat /etc/fstab /dev/mapper/hana-SS3_shared /hana/shared xfs defaults 0 0 /dev/mapper/hana-SS3_log_mnt00001 /hana/log/SS3/mnt00001 xfs relatime,inode64 0 0 /dev/mapper/hana-SS3_data_mnt00001 /hana/data/SS3/mnt00001 xfs relatime,inode64 0 0 /dev/mapper/hana-SS3_data2_mnt00001 /hana/data2/SS3/mnt00001 xfs relatime,inode64 0 0
-
Create mount points and set permissions on the database host.
stlrx300s8-6:/ # mkdir -p /hana/data2/SS3/mnt00001 stlrx300s8-6:/ # chmod –R 777 /hana/data2/SS3
-
Mount the file systems, run the
mount –a
command.
Adding an additional datavolume partition
To add an additional datavolume partition to your tenant database, execute the following SQL statement against the tenant database. Each additional LUN can have a different path:
ALTER SYSTEM ALTER DATAVOLUME ADD PARTITION PATH '/hana/data2/SID/';