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ndb_waiter

NAME

ndb_waiter - wait for MySQL Cluster to reach a given status

SYNOPSIS

ndb_waiter options

DESCRIPTION

ndb_waiter

repeatedly (each 100 milliseconds) prints out the status of all cluster data nodes until either the cluster reaches a given status or the --timeout limit is exceeded, then exits. By default, it waits for the cluster to achieve STARTED status, in which all nodes have started and connected to the cluster. This can be overridden using the --no-contact and --not-started options (see Additional Options).

The node states reported by this utility are as follows:

• NO_CONTACT: The node cannot be contacted.

• UNKNOWN: The node can be contacted, but its status is not yet known. Usually, this means that the node has received a START or RESTART command from the management server, but has not yet acted on it.

• NOT_STARTED: The node has stopped, but remains in contact with the cluster. This is seen when restarting the node using the management client's RESTART command.

• STARTING: The node's ndbd process has started, but the node has not yet joined the cluster.

• STARTED: The node is operational, and has joined the cluster.

• SHUTTING_DOWN: The node is shutting down.

• SINGLE USER MODE: This is shown for all cluster data nodes when the cluster is in single user mode.

Usage:

 ndb_waiter [-c connect_string]
 

Additional Options:

• --no-contact, -n
Instead of waiting for the STARTED state, ndb_waiter continues running until the cluster reaches NO_CONTACT status before exiting.

• --not-started
Instead of waiting for the STARTED state, ndb_waiter continues running until the cluster reaches NOT_STARTED status before exiting.

• --timeout=seconds, -t seconds
Time to wait. The program exits if the desired state is not achieved within this number of seconds. The default is 120 seconds (1200 reporting cycles).

Sample Output. Shown here is the output from ndb_waiter when run against a 4-node cluster in which two nodes have been shut down and then started again manually. Duplicate reports (indicated by "...") are omitted.

 shell> ./ndb_waiter -c localhost
 Connecting to mgmsrv at (localhost)
 State node 1 STARTED
 State node 2 NO_CONTACT
 State node 3 STARTED
 State node 4 NO_CONTACT
 Waiting for cluster enter state STARTED
 ...
 State node 1 STARTED
 State node 2 UNKNOWN
 State node 3 STARTED
 State node 4 NO_CONTACT
 Waiting for cluster enter state STARTED
 ...
 State node 1 STARTED
 State node 2 STARTING
 State node 3 STARTED
 State node 4 NO_CONTACT
 Waiting for cluster enter state STARTED
 ...
 State node 1 STARTED
 State node 2 STARTING
 State node 3 STARTED
 State node 4 UNKNOWN
 Waiting for cluster enter state STARTED
 ...
 State node 1 STARTED
 State node 2 STARTING
 State node 3 STARTED
 State node 4 STARTING
 Waiting for cluster enter state STARTED
 ...
 State node 1 STARTED
 State node 2 STARTED
 State node 3 STARTED
 State node 4 STARTING
 Waiting for cluster enter state STARTED
 ...
 State node 1 STARTED
 State node 2 STARTED
 State node 3 STARTED
 State node 4 STARTED
 Waiting for cluster enter state STARTED
 NDBT_ProgramExit: 0 - OK
 

Note

If no connectstring is specified, then ndb_waiter tries to connect to a management on localhost, and reports Connecting to mgmsrv at (null).

COPYRIGHT

Copyright 2007-2008 MySQL AB, 2009 Sun Microsystems, Inc.

This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.

This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.

SEE ALSO

For more information, please refer to the MySQL Reference Manual, which may already be installed locally and which is also available online at http://dev.mysql.com/doc/.

AUTHOR

Sun Microsystems, Inc. (http://www.mysql.com/).