Backing Up Databases with Veritas NetBackup

For Greenplum Database on Red Hat Enterprise Linux, you can configure Greenplum Database to perform backup and restore operations with Veritas NetBackup. You configure Greenplum Database and NetBackup and then run a Greenplum Database gpcrondump or gpdbrestore command. The following topics describe how to set up NetBackup and back up or restore Greenplum Databases.

About NetBackup Software
Limitations
Configuring Greenplum Database Hosts for NetBackup
Configuring NetBackup for Greenplum Database
Performing a Back Up or Restore with NetBackup
Example NetBackup Back Up and Restore Commands

Parent topic: Parallel Backup with gpcrondump and gpdbrestore

About NetBackup Software

NetBackup includes the following server and client software:

The NetBackup master server manages NetBackup backups, archives, and restores. The master server is responsible for media and device selection for NetBackup.
NetBackup Media servers are the NetBackup device hosts that provide additional storage by allowing NetBackup to use the storage devices that are attached to them.
NetBackup client software that resides on the Greenplum Database hosts that contain data to be backed up.

See the Veritas NetBackup Getting Started Guide for information about NetBackup.

See the Release Notes for information about compatible NetBackup versions for this release of Tanzu Greenplum.

Limitations

NetBackup is not compatible with DDBoost. Both NetBackup and DDBoost cannot be used in a single back up or restore operation.
For incremental back up sets, a full backup and associated incremental backups, the backup set must be on a single device. For example, a backup set must all be on a NetBackup system. The backup set cannot have some backups on a NetBackup system and others on the local file system or a Data Domain system.

Configuring Greenplum Database Hosts for NetBackup

You install and configure NetBackup client software on the Greenplum Database master host and all segment hosts. The NetBackup client software must be able to communicate with the NetBackup server software.

Install the NetBackup client software on Greenplum Database hosts. See the NetBackup installation documentation for information on installing NetBackup clients on UNIX systems.

Set parameters in the NetBackup configuration file /usr/openv/netbackup/bp.conf on the Greenplum Database master and segment hosts. Set the following parameters on each Greenplum Database host.

Parameter	Description
`SERVER`	Host name of the NetBackup Master Server
`MEDIA_SERVER`	Host name of the NetBackup Media Server
`CLIENT_NAME`	Host name of the Greenplum Database Host

See the Veritas NetBackup Administrator's Guide for information about the bp.conf file.

Set the LD_LIBRARY_PATH environment variable for Greenplum Database hosts to use NetBackup client. Greenplum Database installs NetBackup SDK library files that are used with the NetBackup client. To configure Greenplum Database to use the library files that correspond to the version of the NetBackup client that is installed on the hosts, add the following line to the file $GPHOME/greenplum_path.sh:
```
LD_LIBRARY_PATH=$GPHOME/lib/nbu<NN>/lib:$LD_LIBRARY_PATH 
```
Replace the NN with the NetBackup client version that is installed on the host (for example, use 77 for NetBackup 7.7.x).

The LD_LIBRARY_PATH line should be added before this line in $GPHOME/greenplum_path.sh:
```
export LD_LIBRARY_PATH
```
Execute this command to remove the current LD_LIBRARY_PATH value:
```
unset LD_LIBRARY_PATH
```
Execute this command to update the environment variables for Greenplum Database:
```
source $GPHOME/greenplum_path.sh
```

See the Veritas NetBackup Administrator's Guide for information about configuring NetBackup servers.

Ensure that the Greenplum Database hosts are listed as NetBackup clients for the NetBackup server.

In the NetBackup Administration Console, the information for the NetBackup clients, Media Server, and Master Server is in the NetBackup Management node within the Host Properties node.
Configure a NetBackup storage unit. The storage unit must be configured to point to a writable disk location.

In the NetBackup Administration Console, the information for NetBackup storage units is in NetBackup Management node within the Storage node.
Configure a NetBackup backup policy and schedule within the policy.

In the NetBackup Administration Console, the Policy node below the Master Server node is where you create a policy and a schedule for the policy.
- In the Policy Attributes tab, these values are required for Greenplum Database:
  
  The value in the Policy type field must be DataStore
  
  The value in the Policy storage field is the storage unit created in the previous step.
  
  The value in Limit jobs per policy field must be at least 3.
- In the Policy Schedules tab, create a NetBackup schedule for the policy.

Configuring NetBackup for Greenplum Database

See the Veritas NetBackup Administrator's Guide for information about configuring NetBackup servers.

Ensure that the Greenplum Database hosts are listed as NetBackup clients for the NetBackup server.

In the NetBackup Administration Console, the information for the NetBackup clients, Media Server, and Master Server is in NetBackup Management node within the Host Properties node.
Configure a NetBackup storage unit. The storage unit must be configured to point to a writable disk location.

In the NetBackup Administration Console, the information for NetBackup storage units is in NetBackup Management node within the Storage node.
Configure a NetBackup backup policy and schedule within the policy.

In the NetBackup Administration Console, the Policy node below the Master Server node is where you create a policy and a schedule for the policy.
- In the Policy Attributes tab, these values are required for Greenplum Database:
  
  The value in the Policy type field must be DataStore
  
  The value in the Policy storage field is the storage unit created in the previous step.
  
  The value in Limit jobs per policy field must be at least 3.
- In the Policy Schedules tab, create a NetBackup schedule for the policy.

Performing a Back Up or Restore with NetBackup

The Greenplum Database gpcrondump and gpdbrestore utilities support options to back up or restore data to a NetBackup storage unit. When performing a back up, Greenplum Database transfers data files directly to the NetBackup storage unit. No backup data files are created on the Greenplum Database hosts. The backup metadata files are both stored on the hosts and backed up to the NetBackup storage unit.

When performing a restore, the files are retrieved from the NetBackup server, and then restored.

Following are the gpcrondump utility options for NetBackup:

--netbackup-service-host netbackup\_master\_server
--netbackup-policy policy\_name
--netbackup-schedule schedule\_name
--netbackup-block-size size (optional)
--netbackup-keyword keyword (optional)

The gpdbrestore utility provides the following options for NetBackup:

--netbackup-service-host netbackup\_master\_server
--netbackup-block-size size (optional)

Note: When performing a restore operation from NetBackup, you must specify the backup timestamp with the gpdbrestore utility -t option.

The policy name and schedule name are defined on the NetBackup master server. See Configuring NetBackup for Greenplum Database for information about policy name and schedule name. See the Greenplum Database Utility Guide for information about the Greenplum Database utilities.

Note: You must run the gpcrondump or gpdbrestore command during a time window defined for the NetBackup schedule.

During a back up or restore operation, a separate NetBackup job is created for the following types of Greenplum Database data:

Segment data for each segment instance
C database data
Metadata
Post data for the master
State files Global objects (gpcrondump -G option)
Configuration files for master and segments (gpcrondump -g option)
Report files (gpcrondump -h option)

In the NetBackup Administration Console, the Activity Monitor lists NetBackup jobs. For each job, the job detail displays Greenplum Database backup information.

Note: When backing up or restoring a large amount of data, set the NetBackup CLIENT_READ_TIMEOUT option to a value that is at least twice the expected duration of the operation (in seconds). The CLIENT_READ_TIMEOUT default value is 300 seconds (5 minutes).

For example, if a backup takes 3 hours, set the CLIENT_READ_TIMEOUT to 21600 (2 x 3 x 60 x 60). You can use the NetBackup nbgetconfig and nbsetconfig commands on the NetBackup server to view and change the option value.

For information about CLIENT_READ_TIMEOUT and the nbgetconfig, and nbsetconfig commands, see the NetBackup documentation.

Example NetBackup Back Up and Restore Commands

This gpcrondump command backs up the database customer and specifies a NetBackup policy and schedule that are defined on the NetBackup master server nbu_server1. A block size of 1024 bytes is used to transfer data to the NetBackup server.

gpcrondump -x customer --netbackup-service-host=nbu_server1 \
   --netbackup-policy=gpdb_cust --netbackup-schedule=gpdb_backup \
   --netbackup-block-size=1024

This gpdbrestore command restores Greenplum Database data from the data managed by NetBackup master server nbu_server1. The option -t 20170530090000 specifies the timestamp generated by gpcrondump when the backup was created. The -e option specifies that the target database is dropped before it is restored.

gpdbrestore -t 20170530090000 -e --netbackup-service-host=nbu_server1