ndb_waiter(1)

ndb_waiter1

Wait for cluster to reach a given status

Usage

ndb_waiter options

Overview

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).

Author

MySQL AB (http://www.mysql.com/).

From mysql-server-5.0 5.0.51a-24+lenny5 in Debian 5.0 (Lenny). Parsed by carta from the page's man source.