| --- |
| title: hawq restart |
| --- |
| |
| Shuts down and then restarts a HAWQ system after shutdown is complete. |
| |
| ## <a id="topic1__section2"></a>Synopsis |
| |
| ``` pre |
| 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] |
| |
| ``` |
| |
| ``` pre |
| hawq restart -? | -h | --help |
| |
| hawq restart --version |
| ``` |
| |
| ## <a id="topic1__section3"></a>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 |
| |
| <dt>cluster </dt> |
| <dd>Restart a HAWQ cluster.</dd> |
| |
| <dt>master </dt> |
| <dd>Restart HAWQ master.</dd> |
| |
| <dt>segment </dt> |
| <dd>Restart a local segment node.</dd> |
| |
| <dt>standby </dt> |
| <dd>Restart a HAWQ standby.</dd> |
| |
| <dt>allsegments </dt> |
| <dd>Restart all segments.</dd> |
| |
| ## <a id="topic1__section4"></a>Options |
| |
| <dt>-a (do not prompt) </dt> |
| <dd>Do not prompt the user for confirmation.</dd> |
| |
| <dt>-l, -\\\-logdir \<logfile\_directory\> </dt> |
| <dd>Specifies the log directory for logs of the management tools. The default is `~/hawq/Adminlogs/`.</dd> |
| |
| <dt>-q, -\\\-quiet </dt> |
| <dd>Run in quiet mode. Command output is not displayed on the screen, but is still written to the log file.</dd> |
| |
| <dt>-v, -\\\-verbose </dt> |
| <dd>Displays detailed status, progress and error messages output by the utility.</dd> |
| |
| <dt>-t, -\\\-timeout \<timeout\_seconds\> </dt> |
| <dd>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 60 seconds.</dd> |
| |
| <dt>-M, -\\\-mode smart | fast | immediate </dt> |
| <dd>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.</dd> |
| |
| <dt>-u, -\\\-reload </dt> |
| <dd>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.</dd> |
| |
| <dt>-R, -\\\-restrict </dt> |
| <dd>Starts HAWQ in restricted mode (only database superusers are allowed to connect).</dd> |
| |
| <dt>-U, -\\\-special-mode maintenance </dt> |
| <dd>(Superuser only) Start HAWQ in \[maintenance | upgrade\] mode. In maintenance mode, the `gp_maintenance_conn` parameter is set.</dd> |
| |
| <dt>-\\\-ignore\-bad\-hosts cluster | allsegments </dt> |
| <dd>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.</dd> |
| |
| <dt>-? , -h , -\\\-help (help) </dt> |
| <dd>Displays the online help.</dd> |
| |
| <dt>-\\\-version (show utility version) </dt> |
| <dd>Displays the version of this utility.</dd> |
| |
| ## <a id="topic1__section5"></a>Examples |
| |
| Restart a HAWQ cluster: |
| |
| ``` shell |
| $ hawq restart cluster |
| ``` |
| |
| Restart a HAWQ system in restricted mode (only allow superuser connections): |
| |
| ``` shell |
| $ hawq restart cluster -R |
| ``` |
| |
| Start the HAWQ master instance only and connect in utility mode: |
| |
| ``` shell |
| $ hawq start master -m PGOPTIONS='-c gp_session_role=utility' psql |
| ``` |
| |
| ## <a id="topic1__section6"></a>See Also |
| |
| [hawq stop](hawqstop.html#topic1), [hawq start](hawqstart.html#topic1) |