Creating the Data Storage Areas v7.5

Describes how to create the directory locations where WarehousePG data is stored for each coordinator, standby, and segment instance.

Parent topic: Installing and Upgrading WarehousePG

Creating Data Storage Areas on the Coordinator and Standby Coordinator Hosts

A data storage area is required on the WarehousePG coordinator and standby coordinator hosts to store WarehousePG cluster data such as catalog data and other system metadata.

To create the data directory location on the coordinator

The data directory location on the coordinator is different than those on the segments. The coordinator does not store any user data, only the system catalog tables and system metadata are stored on the coordinator instance, therefore you do not need to designate as much storage space as on the segments.

1. Create or choose a directory that will serve as your coordinator data storage area. This directory should have sufficient disk space for your data and be owned by the gpadmin user and group. For example, run the following command using sudo:

   → WrapCopy

   sudo mkdir -p /data/coordinator

2. Change ownership of this directory, and any parent directories you created, to the gpadmin user. For example:

   → WrapCopy

   sudo chown gpadmin:gpadmin /data
   sudo chown -R gpadmin:gpadmin /data/coordinator

3. As the gpadmin user, use gpssh to create the coordinator data directory location on your standby coordinator as well. For example:

   → WrapCopy

   gpssh -h scdw -e 'sudo mkdir -p /data/coordinator'
   gpssh -h scdw -e 'sudo chown -R gpadmin:gpadmin /data/coordinator'

Creating Data Storage Areas on Segment Hosts

Data storage areas are required on the WarehousePG segment hosts for primary segments. Separate storage areas are required for mirror segments.

To create the data directory locations on all segment hosts

1. On the coordinator host, switch to the gpadmin user and source the greenplum_path.sh file.

   → WrapCopy

   sudo -iu gpadmin
   source /usr/local/whpg/greenplum_path.sh

   Note

   Logging in as root with su fails on hosts where root login is deactivated, such as Amazon EC2 instances. Use sudo for the gpssh commands on the remote hosts instead, so you can run them as gpadmin, provided gpadmin has sudo privilege as described in Creating the WarehousePG Administrative User.

2. Create a file called hostfile_gpssh_segonly. This file should have only one machine configured host name for each segment host. For example, if you have three segment hosts:

   → WrapCopy

   sdw1
   sdw2
   sdw3

3. Using gpssh, create the primary and mirror data directory locations on all segment hosts at once using the hostfile_gpssh_segonly file you just created. For example:

   → WrapCopy

   gpssh -f hostfile_gpssh_segonly -e 'sudo mkdir -p /data1/primary'
   gpssh -f hostfile_gpssh_segonly -e 'sudo mkdir -p /data2/primary'
   gpssh -f hostfile_gpssh_segonly -e 'sudo mkdir -p /data1/mirror'
   gpssh -f hostfile_gpssh_segonly -e 'sudo mkdir -p /data2/mirror'
   gpssh -f hostfile_gpssh_segonly -e 'sudo chown -R gpadmin:gpadmin /data1 /data2'

   Caution

   Use chown -R gpadmin:gpadmin /data1 /data2 rather than chown -R gpadmin /data*/*. The latter sets only the owner, not the group, so the primary and mirror directories stay in the root group. Setting both the owner and group to gpadmin avoids permission problems later.

Next Steps

• Validating the WHPG Cluster
• Initializing WarehousePG