Initializing Greenplum

Before initializing the Greenplum database, modify the parameters in the initialization configuration file and then run the initialization command. Perform the operations in this section on the master node.

To initialize Greenplum, perform the following steps:

Open the initialization configuration file /home/gpadmin/init.config.
```
vim /home/gpadmin/init.config
```

Press i to enter the insert mode and add the following content:

ARRAY_NAME="Greenplum Cluster"
SEG_PREFIX=gpseg
PORT_BASE=40000
declare -a DATA_DIRECTORY=(/data/gpdb/segdata /data/gpdb/segdata)
MASTER_HOSTNAME=gp-mdw
MASTER_DIRECTORY=/data/gpdb/master
MASTER_PORT=5432
TRUSTED_SHELL=ssh
CHECK_POINT_SEGMENTS=8
ENCODING=UNICODE
DATABASE_NAME=gpdb
MACHINE_LIST_FILE=/data/gpdb/seg_hosts

**Table 1** Parameters in the configuration file
Parameter	Description
ARRAY_NAME	Sets the name of the Greenplum cluster.
SEG_PREFIX	Sets the prefix name of the segment database.
PORT_BASE	Sets the start port number of the segment database.
DATA_DIRECTORY	Defines the array of the segment data directory. Greenplum starts a segment in each data directory.
MASTER_HOSTNAME	Specifies the host name of the master node.
MASTER_DIRECTORY	Specifies the data directory of the master node.
MASTER_PORT	Specifies the port number of the master node. This port is usually used by services.
TRUSTED_SHELL	Sets the value to ssh, which means SSH is used for communication between nodes during initialization.
CHECK_POINT_SEGMENTS	Specifies the number of segments to be written at checkpoints.
ENCODING	Sets the character encoding of the database. UNICODE is used.
DATABASE_NAME	Specifies the name of the database to be created after initialization.
MACHINE_LIST_FILE	Specifies the path of the configuration file that contains information about all hosts in the cluster.

Press Esc, type :wq!, and press Enter to save the file and exit.

Initialize the database.

gpinitsystem -c /home/gpadmin/init.config -a

Parent topic: Installing Greenplum