gpinitsystem

Initializes a LightDB-A Database system using configuration parameters specified in the gpinitsystem_config file.

Synopsis

gpinitsystem -c <cluster_configuration_file> 
            [-h <hostfile_gpinitsystem>]
            [-B <parallel_processes>] 
            [-p <postgresql_conf_param_file>]
            [-s <standby_coordinator_host>
                [-P <standby_coordinator_port>]
                [-S <standby_coordinator_datadir> | --standby_datadir=<standby_coordinator_datadir>]]
            [-m <number> | --max_connections=number>]
            [-b <size> | --shared_buffers=<size>]
            [-n <locale> | --locale=<locale>] [--lc-collate=<locale>] 
            [--lc-ctype=<locale>] [--lc-messages=<locale>] 
            [--lc-monetary=<locale>] [--lc-numeric=<locale>] 
            [--lc-time=<locale>] [-e <password> | --su_password=<password>] 
            [--mirror-mode={group|spread}] [-a] [-q] [-l <logfile_directory>] [-D]
            [-I <input_configuration_file>]
            [-O <output_configuration_file>]

gpinitsystem -v | --version

gpinitsystem -? | --help

Description

The gpinitsystem utility creates a LightDB-A Database instance or writes an input configuration file using the values defined in a cluster configuration file and any command-line options that you provide. See Initialization Configuration File Format for more information about the configuration file. Before running this utility, make sure that you have installed the LightDB-A Database software on all the hosts in the array.

With the <-O output_configuration_file> option, gpinitsystem writes all provided configuration information to the specified output file. This file can be used with the -I option to create a new cluster or re-create a cluster from a backed up configuration. See Initialization Configuration File Format for more information.

In a LightDB-A Database DBMS, each database instance (the coordinator instance and all segment instances) must be initialized across all of the hosts in the system in such a way that they can all work together as a unified DBMS. The gpinitsystem utility takes care of initializing the LightDB-A coordinator and each segment instance, and configuring the system as a whole.

Before running gpinitsystem, you must set the $GPHOME environment variable to point to the location of your LightDB-A Database installation on the coordinator host and exchange SSH keys between all host addresses in the array using gpssh-exkeys.

This utility performs the following tasks:

Verifies that the parameters in the configuration file are correct.
Ensures that a connection can be established to each host address. If a host address cannot be reached, the utility will exit.
Verifies the locale settings.
Displays the configuration that will be used and prompts the user for confirmation.
Initializes the coordinator instance.
Initializes the standby coordinator instance (if specified).
Initializes the primary segment instances.
Initializes the mirror segment instances (if mirroring is configured).
Configures the LightDB-A Database system and checks for errors.
Starts the LightDB-A Database system.

Note This utility uses secure shell (SSH) connections between systems to perform its tasks. In large LightDB-A Database deployments, cloud deployments, or deployments with a large number of segments per host, this utility may exceed the host’s maximum threshold for unauthenticated connections. Consider updating the SSH MaxStartups and MaxSessions configuration parameters to increase this threshold. For more information about SSH configuration options, refer to the SSH documentation for your Linux distribution.

Options

-a : Do not prompt the user for confirmation.

-B parallel_processes : The number of segments to create in parallel. If not specified, the utility will start up to 4 parallel processes at a time.

-c cluster_configuration_file : Required. The full path and filename of the configuration file, which contains all of the defined parameters to configure and initialize a new LightDB-A Database system. See Initialization Configuration File Format for a description of this file. You must provide either the -c <cluster_configuration_file> option or the -I <input_configuration_file> option to gpinitsystem.

-D : Sets log output level to debug.

-h hostfile_gpinitsystem : Optional. The full path and filename of a file that contains the host addresses of your segment hosts. If not specified on the command line, you can specify the host file using the MACHINE_LIST_FILE parameter in the gpinitsystem_config file.

-I input_configuration_file : The full path and filename of an input configuration file, which defines the LightDB-A Database host systems, the coordinator instance and segment instances on the hosts, using the QD_PRIMARY_ARRAY, PRIMARY_ARRAY, and MIRROR_ARRAY parameters. The input configuration file is typically created by using gpinitsystem with the -O output\_configuration\_file option. Edit those parameters in order to initialize a new cluster or re-create a cluster from a backed up configuration. You must provide either the -c <cluster_configuration_file> option or the -I <input_configuration_file> option to gpinitsystem.

-n locale | –locale=locale : Sets the default locale used by LightDB-A Database. If not specified, the default locale is en_US.utf8. A locale identifier consists of a language identifier and a region identifier, and optionally a character set encoding. For example, sv_SE is Swedish as spoken in Sweden, en_US is U.S. English, and fr_CA is French Canadian. If more than one character set can be useful for a locale, then the specifications look like this: en_US.UTF-8 (locale specification and character set encoding). On most systems, the command locale will show the locale environment settings and locale -a will show a list of all available locales.

–lc-collate=locale : Similar to --locale, but sets the locale used for collation (sorting data). The sort order cannot be changed after LightDB-A Database is initialized, so it is important to choose a collation locale that is compatible with the character set encodings that you plan to use for your data. There is a special collation name of C or POSIX (byte-order sorting as opposed to dictionary-order sorting). The C collation can be used with any character encoding.

–lc-ctype=locale : Similar to --locale, but sets the locale used for character classification (what character sequences are valid and how they are interpreted). This cannot be changed after LightDB-A Database is initialized, so it is important to choose a character classification locale that is compatible with the data you plan to store in LightDB-A Database.

–lc-messages=locale : Similar to --locale, but sets the locale used for messages output by LightDB-A Database. The current version of LightDB-A Database does not support multiple locales for output messages (all messages are in English), so changing this setting will not have any effect.

–lc-monetary=locale : Similar to --locale, but sets the locale used for formatting currency amounts.

–lc-numeric=locale : Similar to --locale, but sets the locale used for formatting numbers.

–lc-time=locale : Similar to --locale, but sets the locale used for formatting dates and times.

-l logfile_directory : The directory to write the log file. Defaults to ~/ltaAdminLogs.

-m number | –max_connections=number : Sets the maximum number of client connections allowed to the coordinator. The default is 250.

-O output_configuration_file : Optional, used during new cluster initialization. This option writes the cluster_configuration_file information (used with -c) to the specified output_configuration_file. This file defines the LightDB-A Database members using the QD_PRIMARY_ARRAY, PRIMARY_ARRAY, and MIRROR_ARRAY parameters. Use this file as a template for the -I input_configuration_file option. See Examples for more information.

-p postgresql_conf_param_file : Optional. The name of a file that contains postgresql.conf parameter settings that you want to set for LightDB-A Database. These settings will be used when the individual coordinator and segment instances are initialized. You can also set parameters after initialization using the gpconfig utility.

-q : Run in quiet mode. Command output is not displayed on the screen, but is still written to the log file.

-b size | –shared_buffers=size : Sets the amount of memory a LightDB-A server instance uses for shared memory buffers. You can specify sizing in kilobytes (kB), megabytes (MB) or gigabytes (GB). The default is 125MB.

-s standby_coordinator_host : Optional. If you wish to configure a backup coordinator instance, specify the host name using this option. The LightDB-A Database software must already be installed and configured on this host.

-P standby_coordinator_port : If you configure a standby coordinator instance with -s, specify its port number using this option. The default port is the same as the coordinator port. To run the standby and coordinator on the same host, you must use this option to specify a different port for the standby. The LightDB-A Database software must already be installed and configured on the standby host.

-S standby_coordinator_datadir | –standby_dir=standby_coordinator_datadir : If you configure a standby coordinator host with -s, use this option to specify its data directory. If you configure a standby on the same host as the coordinator instance, the coordinator and standby must have separate data directories.

-e superuser_password | –su_password=superuser_password : Use this option to specify the password to set for the LightDB-A Database superuser account (such as gpadmin). If this option is not specified, the default password gparray is assigned to the superuser account. You can use the ALTER ROLE command to change the password at a later time.

Recommended security best practices:

-   Do not use the default password option for production environments.
-   Change the password immediately after installation.

–mirror-mode={group|spread} : Use this option to specify the placement of mirror segment instances on the segment hosts. The default, group, groups the mirror segments for all of a host’s primary segments on a single alternate host. spread spreads mirror segments for the primary segments on a host across different hosts in the LightDB-A Database array. Spreading is only allowed if the number of hosts is greater than the number of segment instances per host. See Overview of Segment Mirroring for information about LightDB-A Database mirroring strategies.

-v | –version : Print the gpinitsystem version and exit.

-? | –help : Show help about gpinitsystem command line arguments, and exit.

Initialization Configuration File Format

gpinitsystem requires a cluster configuration file with the following parameters defined. An example initialization configuration file can be found in $GPHOME/docs/cli_help/gpconfigs/gpinitsystem_config.

To avoid port conflicts between LightDB-A Database and other applications, the LightDB-A Database port numbers should not be in the range specified by the operating system parameter net.ipv4.ip_local_port_range. For example, if net.ipv4.ip_local_port_range = 10000 65535, you could set LightDB-A Database base port numbers to these values.

PORT_BASE = 6000
MIRROR_PORT_BASE = 7000

MACHINE_LIST_FILE : Optional. Can be used in place of the -h option. This specifies the file that contains the list of the segment host address names that comprise the LightDB-A Database system. The coordinator host is assumed to be the host from which you are running the utility and should not be included in this file. If your segment hosts have multiple network interfaces, then this file would include all addresses for the host. Give the absolute path to the file.

SEG_PREFIX : Required. This specifies a prefix that will be used to name the data directories on the coordinator and segment instances. The naming convention for data directories in a LightDB-A Database system is SEG_PREFIXnumber where number starts with 0 for segment instances (the coordinator is always -1). So for example, if you choose the prefix gpseg, your coordinator instance data directory would be named gpseg-1, and the segment instances would be named gpseg0, gpseg1, gpseg2, gpseg3, and so on.

PORT_BASE : Required. This specifies the base number by which primary segment port numbers are calculated. The first primary segment port on a host is set as PORT_BASE, and then incremented by one for each additional primary segment on that host. Valid values range from 1 through 65535.

DATA_DIRECTORY : Required. This specifies the data storage location(s) where the utility will create the primary segment data directories. The number of locations in the list dictate the number of primary segments that will get created per physical host (if multiple addresses for a host are listed in the host file, the number of segments will be spread evenly across the specified interface addresses). It is OK to list the same data storage area multiple times if you want your data directories created in the same location. The user who runs gpinitsystem (for example, the gpadmin user) must have permission to write to these directories. For example, this will create six primary segments per host:

: declare -a DATA_DIRECTORY=(/data1/primary /data1/primary /data1/primary /data2/primary /data2/primary /data2/primary)

MASTER_HOSTNAME : Required. The host name of the coordinator instance. This host name must exactly match the configured host name of the machine (run the hostname command to determine the correct hostname).

MASTER_DIRECTORY : Required. This specifies the location where the data directory will be created on the coordinator host. You must make sure that the user who runs gpinitsystem (for example, the gpadmin user) has permissions to write to this directory.

MASTER_PORT : Required. The port number for the coordinator instance. This is the port number that users and client connections will use when accessing the LightDB-A Database system.

TRUSTED_SHELL : Required. The shell the gpinitsystem utility uses to run commands on remote hosts. Allowed values are ssh. You must set up your trusted host environment before running the gpinitsystem utility (you can use gpssh-exkeys to do this).

ENCODING : Required. The character set encoding to use. This character set must be compatible with the --locale settings used, especially --lc-collate and --lc-ctype. LightDB-A Database supports the same character sets as PostgreSQL.

DATABASE_NAME : Optional. The name of a LightDB-A Database database to create after the system is initialized. You can always create a database later using the CREATE DATABASE command or the createdb utility.

MIRROR_PORT_BASE : Optional. This specifies the base number by which mirror segment port numbers are calculated. The first mirror segment port on a host is set as MIRROR_PORT_BASE, and then incremented by one for each additional mirror segment on that host. Valid values range from 1 through 65535 and cannot conflict with the ports calculated by PORT_BASE.

MIRROR_DATA_DIRECTORY : Optional. This specifies the data storage location(s) where the utility will create the mirror segment data directories. There must be the same number of data directories declared for mirror segment instances as for primary segment instances (see the DATA_DIRECTORY parameter). The user who runs gpinitsystem (for example, the gpadmin user) must have permission to write to these directories. For example:

: declare -a MIRROR_DATA_DIRECTORY=(/data1/mirror /data1/mirror /data1/mirror /data2/mirror /data2/mirror /data2/mirror)

QD_PRIMARY_ARRAY, PRIMARY_ARRAY, MIRROR_ARRAY : Required when using input_configuration file with -I option. These parameters specify the LightDB-A Database coordinator host, the primary segment, and the mirror segment hosts respectively. During new cluster initialization, use the gpinitsystem -O output\_configuration\_file to populate QD_PRIMARY_ARRAY, PRIMARY_ARRAY, MIRROR_ARRAY.

: To initialize a new cluster or re-create a cluster from a backed up configuration, edit these values in the input configuration file used with the gpinitsystem -I input\_configuration\_file option. Use one of the following formats to specify the host information:

```
<hostname>~<address>~<port>~<data_directory>/<seg_prefix<segment_id>~<dbid>~<content_id>
```

or

```
<host>~<port>~<data_directory>/<seg_prefix<segment_id>~<dbid>~<content_id>
```

: The first format populates the hostname and address fields in the gp_segment_configuration catalog table with the hostname and address values provided in the input configuration file. The second format populates hostname and address fields with the same value, derived from host.

: The LightDB-A Database coordinator always uses the value -1 for the segment ID and content ID. For example, seg_prefix and dbid values for QD_PRIMARY_ARRAY use -1 to indicate the coordinator instance:

```
QD_PRIMARY_ARRAY=cdw~cdw~5432~/gpdata/coordinator/gpseg-1~1~-1
declare -a PRIMARY_ARRAY=(
sdw1~sdw1~40000~/gpdata/data1/gpseg0~2~0
sdw1~sdw1~40001~/gpdata/data2/gpseg1~3~1
sdw2~sdw2~40000~/gpdata/data1/gpseg2~4~2
sdw2~sdw2~40001~/gpdata/data2/gpseg3~5~3
)
declare -a MIRROR_ARRAY=(
sdw2~sdw2~50000~/gpdata/mirror1/gpseg0~6~0
sdw2~sdw2~50001~/gpdata/mirror2/gpseg1~7~1
sdw1~sdw1~50000~/gpdata/mirror1/gpseg2~8~2
sdw1~sdw1~50001~/gpdata/mirror2/gpseg3~9~3
)
```

: To re-create a cluster using a known LightDB-A Database system configuration, you can edit the segment and content IDs to match the values of the system.

HEAP_CHECKSUM : Optional. This parameter specifies if checksums are enabled for heap data. When enabled, checksums are calculated for heap storage in all databases, enabling LightDB-A Database to detect corruption in the I/O system. This option is set when the system is initialized and cannot be changed later.

: The HEAP_CHECKSUM option is on by default and turning it off is strongly discouraged. If you set this option to off, data corruption in storage can go undetected and make recovery much more difficult.

: To determine if heap checksums are enabled in a LightDB-A Database system, you can query the data_checksums server configuration parameter with the gpconfig management utility:

```
$ gpconfig -s data_checksums
```

HBA_HOSTNAMES : Optional. This parameter controls whether gpinitsystem uses IP addresses or host names in the pg_hba.conf file when updating the file with addresses that can connect to LightDB-A Database. The default value is 0, the utility uses IP addresses when updating the file. When initializing a LightDB-A Database system, specify HBA_HOSTNAMES=1 to have the utility use host names in the pg_hba.conf file.

: For information about how LightDB-A Database resolves host names in the pg_hba.conf file, see Configuring Client Authentication.

Specifying Hosts using Hostnames or IP Addresses

When initializing a LightDB-A Database system with gpinitsystem, you can specify segment hosts using either hostnames or IP addresses. For example, you can use hostnames or IP addresses in the file specified with the -h option.

If you specify a hostname, the resolution of the hostname to an IP address should be done locally for security. For example, you should use entries in a local /etc/hosts file to map a hostname to an IP address. The resolution of a hostname to an IP address should not be performed by an external service such as a public DNS server. You must stop the LightDB-A system before you change the mapping of a hostname to a different IP address.
If you specify an IP address, the address should not be changed after the initial configuration. When segment mirroring is enabled, replication from the primary to the mirror segment will fail if the IP address changes from the configured value. For this reason, you should use a hostname when initializing a LightDB-A Database system unless you have a specific requirement to use IP addresses.

When initializing the LightDB-A Database system, gpinitsystem uses the initialization information to populate the gp_segment_configuration catalog table and adds hosts to the pg_hba.conf file. By default, the host IP address is added to the file. Specify the gpinitsystem configuration file parameter HBA_HOSTNAMES=1 to add hostnames to the file.

LightDB-A Database uses the address value of the gp_segment_configuration catalog table when looking up host systems for LightDB-A interconnect (internal) communication between the coordinator and segment instances and between segment instances, and for other internal communication.

Examples

Initialize a LightDB-A Database system by supplying a cluster configuration file and a segment host address file, and set up a spread mirroring (--mirror-mode=spread) configuration:

$ gpinitsystem -c gpinitsystem_config -h hostfile_gpinitsystem --mirror-mode=spread

Initialize a LightDB-A Database system and set the superuser remote password:

$ gpinitsystem -c gpinitsystem_config -h hostfile_gpinitsystem --su-password=mypassword

Initialize a LightDB-A Database system with an optional standby coordinator host:

$ gpinitsystem -c gpinitsystem_config -h hostfile_gpinitsystem -s host09

Initialize a LightDB-A Database system and write the provided configuration to an output file, for example cluster_init.config:

$ gpinitsystem -c gpinitsystem_config -h hostfile_gpinitsystem -O cluster_init.config

The output file uses the QD_PRIMARY_ARRAY and PRIMARY_ARRAY parameters to define coordinator and segment hosts:

TRUSTED_SHELL=ssh
CHECK_POINT_SEGMENTS=8
ENCODING=UNICODE
SEG_PREFIX=gpseg
HEAP_CHECKSUM=on
HBA_HOSTNAMES=0
QD_PRIMARY_ARRAY=cdw~cdw.local~5433~/data/coordinator1/gpseg-1~1~-1
declare -a PRIMARY_ARRAY=(
cdw~cdw.local~6001~/data/primary1/gpseg0~2~0
)
declare -a MIRROR_ARRAY=(
cdw~cdw.local~7001~/data/mirror1/gpseg0~3~0
)

Initialize a LightDB-A Database using an input configuration file (a file that defines the LightDB-A Database cluster) using QD_PRIMARY_ARRAY and PRIMARY_ARRAY parameters:

$ gpinitsystem -I cluster_init.config

The following example uses a host system configured with multiple NICs. If host systems are configured with multiple NICs, you can initialize a LightDB-A Database system to use each NIC as a LightDB-A host system. You must ensure that the host systems are configured with sufficient resources to support all the segment instances being added to the host. Also, if high availability is enabled, you must ensure that the LightDB-A system configuration supports failover if a host system fails. For information about LightDB-A Database mirroring schemes, see ../../best_practices/ha.html#topic_ngz_qf4_tt.

For this simple coordinator and segment instance configuration, the host system gp6m is configured with two NICs gp6m-1 and gp6m-2. In the configuration, the QD_PRIMARY_ARRAY parameter defines the coordinator segment using gp6m-1. The PRIMARY_ARRAY and MIRROR_ARRAY parameters use gp6m-2 to define a primary and mirror segment instance.

QD_PRIMARY_ARRAY=gp6m~gp6m-1~5432~/data/coordinator/gpseg-1~1~-1
declare -a PRIMARY_ARRAY=(
gp6m~gp6m-2~40000~/data/data1/gpseg0~2~0
gp6s~gp6s~40000~/data/data1/gpseg1~3~1
)
declare -a MIRROR_ARRAY=(
gp6s~gp6s~50000~/data/mirror1/gpseg0~4~0
gp6m~gp6m-2~50000~/data/mirror1/gpseg1~5~1
)