hawq restart

Shuts down and then restarts a HAWQ system after shutdown is complete.

Synopsis

hawq restart <object> [-l|--logdir <logfile_directory>] [-q|--quiet] [-v|--verbose]    
        [-M|--mode smart | fast | immediate] [-u|--reload] [-m|--masteronly] [-R|--restrict]
        [-t|--timeout <timeout_seconds>]  [-U | --special-mode maintenance]
        [--ignore-bad-hosts cluster | allsegments]

hawq restart -? | -h | --help 
hawq restart --version

Description

The hawq restart utility is used to shut down and restart the HAWQ server processes. It is essentially equivalent to performing a hawq stop -M smart operation followed by hawq start.

The <object> in the command specifies what entity should be started: e.g. a cluster, a segment, the master node, standby node, or all segments in the cluster.

When the hawq restart command runs, the utility uploads changes made to the master pg_hba.conf file or to the runtime configuration parameters in the master hawq-site.xml file without interruption of service. Note that any active sessions will not pick up the changes until they reconnect to the database.

Objects

cluster

Restart a HAWQ cluster.

master

Restart HAWQ master.

segment

Restart a local segment node.

standby

Restart a HAWQ standby.

allsegments

Restart all segments.

Options

-a (do not prompt)

Do not prompt the user for confirmation.

-l, —logdir <logfile_directory>

Specifies the log directory for logs of the management tools. The default is ~/hawqAdminLogs/.

-q, —quiet

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

-v, —verbose

Displays detailed status, progress and error messages output by the utility.

-t, —timeout <timeout_seconds>

Specifies a timeout in seconds to wait for a segment instance to start up. If a segment instance was shutdown abnormally (due to power failure or killing its postgres database listener process, for example), it may take longer to start up due to the database recovery and validation process. If not specified, the default timeout is 600 seconds.

-M, —mode smart | fast | immediate

Smart shutdown is the default. Shutdown fails with a warning message, if active connections are found.

Fast shut down interrupts and rolls back any transactions currently in progress .

Immediate shutdown aborts transactions in progress and kills all postgres processes without allowing the database server to complete transaction processing or clean up any temporary or in-process work files. Because of this, immediate shutdown is not recommended. In some instances, it can cause database corruption that requires manual recovery.

-u, —reload

Utility mode. This mode runs on the master, only, and only allows incoming sessions that specify gp_session_role=utility. It allows bash scripts to reload the parameter values and connect but protects the system from normal clients who might be trying to connect to the system during startup.

-R, —restrict

Starts HAWQ in restricted mode (only database superusers are allowed to connect).

-U, —special-mode maintenance

(Superuser only) Start HAWQ in [maintenance | upgrade] mode. In maintenance mode, the gp_maintenance_conn parameter is set.

--ignore-bad-hosts cluster | allsegments

Overrides copying configuration files to a host on which SSH validation fails. If ssh to a skipped host is reestablished, make sure the configuration files are re-synched once it is reachable.

-? , -h , —help (help)

Displays the online help.

--version (show utility version)

Displays the version of this utility.

Examples

Restart a HAWQ cluster:

$ hawq restart cluster

Restart a HAWQ system in restricted mode (only allow superuser connections):

$ hawq restart cluster -R

Start the HAWQ master instance only and connect in utility mode:

$ hawq start master -m PGOPTIONS='-c gp_session_role=utility' psql

See Also

hawq stop, hawq start