Off-host alternate client, VVR method (Solaris SPARC, HP-UX)
Based on this VVR configuration, the typical flow during the Snapshot Client backup for SAP:
The database shuts down or tablespaces are put in backup mode in the production host.
Replication is stopped between primary disk D1 and replication disk D2.
The alternate client off-host takes the snapshot of the replication database from disk D2 to mirror disk D3.
The production database in primary disk D1 is created online.
The mirror disk D3 is split to perform backup from the snapshot to the backup media.
The snapshot from the mirror disk D3 is then joined back to the volume in replication disk D2.
Then the storage replication log (SRL) resync happens in primary disk D1 and secondary disk D2.
Finally, replication resumes.
Before configuring this method, install and configure the following:
Install and configure the following on the production database host:
Install NetBackup Client, NetBackup Snapshot Client, and the NetBackup for SAP Agent
Configure the production database (Oracle).
You can install the NetBackup master server on a separate host
Install the following on the alternate client (off-host):
Install NetBackup Client and NetBackup Snapshot Client. The NetBackup for SAP Agent is not required.
The NetBackup media server. You can install the media server on the same host or on separate host where you want to attach the backup media.
The following procedures describe how to configure both the volume replicator primary and the volume replicator secondary.
To configure the volume replicator primary (production database host)
- Attach the external primary disk D1 to the volume replicator primary, and create a VM disk group using the following command:
root@primary# vxdg init diskgroup [cds=on|off] diskname=devicename
- Create a data volume in primary disk D1 using the following command:
root@primary# vxassist -g diskgroup make volume size
By default, it creates two copies that require two disks in one group. To override the default, enter the following command:
root@primary # vxassist -g diskgroup addlog volume logtype=dcm nlog=1
- Create the VxFS file system on this volume and mount it using the following commands:
root@primary# mkfs -F vxfs /dev/vx/rdsk/diskgroup/volume root@primary# mount -F vxfs /dev/vx/dsk/diskgroup/volume mnt
- Create the SAP production database on this volume.
- Create a Storage Replicator Log (SRL) volume in primary disk D1 using the following command:
root@primary# vxassist -g diskgroup make volume_srl size
To configure the volume replicator secondary (alternate client off-host)
- Attach the external replication disk D2 to the volume replicator secondary and create the VM disk group using the following command:
root@secondary# vxdg init diskgroup [cds=on|off] diskname=devicename
- Create a data volume in replication disk D2 using the following command:
root@secondary # vxassist -g diskgroup make volume size
By default, it creates two copies that require two disks in one group. To override the default, enter the following command:
root@secondary# vxassist -g diskgroup addlog volume logtype=dcm nlog=1
- Create a Storage Replicator Log (SRL) volume in the replication disk D2 using the following command:
root@secondary# vxassist -g diskgroup make volume_srl size
- Create the primary replicated volume group (RVG) specifying the data volume(s) and the SRL volume. On the volume replicator primary (production database host), run the following command:
The names of the disk group and volumes must be same as on the primary host.
root@primary# vradmin -g diskgroup createpri rvg_name data_volumes(s) srl_volume
- Ensure that authentication can complete.
Before you add a new secondary host (by using the addsec) or overwrite data on a remote host (by using the syncvol), vradmin performs some authentication. This process checks that the /etc/vx/vras/.rdg file on the remote host contains an entry for the primary disk group ID. The vradmin addsec or syncvol command fails if the /etc/vx/vras/.rdg file on the remote host does not have such an entry.
If authentication cannot complete, do the following:
Add the primary disk group ID to the /etc/vx/vras/.rdg file on the remote host.
To find disk group ID, run the vxprint -l diskgroup_name command on the primary.
Ensure that the /etc/hosts file has entries of primary and secondary host names in both hosts.
- Add the secondary RVG to form the replicated data set (RDS) using the following command:
root@primary# vradmin -g diskgroup addsec rvg_name primary_hostname secondary_hostname
- Start replication between the volume replicator primary and secondary using the following command:
root@primary# vradmin -g group_1 -a startrep v1_rvg
- Attach the external mirror disk D3 to the alternate client for taking a snapshot mirror.
- On the volume replicator secondary (alternate client off-host), start the snap for the data volume using the following command:
root@secondary# vxassist - g diskgroup -b snapstart volume
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