The State Threads is a small application library which provides a foundation for writing fast and highly scalable Internet applications (such as Web servers, proxy servers, mail transfer agents, etc.) on UNIX-like platforms. It offers a threading API for structuring a network application as an event-driven state machine.License: Mozilla Public License (MPL)Changes:
This release adds support for kqueue and epoll on platforms that support them, and the ability to choose the event notification system at program startup. It also adds the functions st_writev_resid(), st_readv_resid(), and st_readv(). It incorporates public definitions of ST_UTIME_NO_TIMEOUT and ST_UTIME_NO_WAIT. The documentation has been fixed.
NDB_WAITER(1) MySQL Database System NDB_WAITER(1)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.
The node states reported by this utility are as follows:
o NO_CONTACT: The node cannot be contacted.
o 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.
o 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.
o STARTING: The node's ndbd process has started, but the node has not yet joined the cluster.
o STARTED: The node is operational, and has joined the cluster.
o SHUTTING_DOWN: The node is shutting down.
o SINGLE USER MODE: This is shown for all cluster data nodes when the cluster is in single user mode.
The following table includes options that are specific to the MySQL Cluster native backup restoration program ndb_waiter. Additional
descriptions follow the table. For options common to most MySQL Cluster programs (including ndb_waiter), see Options Common to MySQL
Cluster Programs(1).
Table 17.28. ndb_waiter Options and Variables: MySQL Cluster NDB 7.2
+---------------------------+--------------------------------------+-------------------------------------+
|Format | Description | Added / Removed |
+---------------------------+--------------------------------------+-------------------------------------+
| | Wait for cluster to reach NO CONTACT | |
| --no-contact, | state | All MySQL 5.5 based releases |
| | | |
| -n | | |
+---------------------------+--------------------------------------+-------------------------------------+
| | Wait for cluster to reach NOT | |
| --not-started | STARTED state | All MySQL 5.5 based releases |
+---------------------------+--------------------------------------+-------------------------------------+
| | Wait for cluster to enter single | |
| --single-user | user mode | All MySQL 5.5 based releases |
+---------------------------+--------------------------------------+-------------------------------------+
| | Wait this many seconds, then exit | |
| --timeout=#, | whether or not cluster has reached | All MySQL 5.5 based releases |
| | desired state; default | |
| -t | is 2 minutes (120 seconds) | |
+---------------------------+--------------------------------------+-------------------------------------+
| | List of nodes not to be waited for. | |
| --nowait-nodes=list | | All MySQL 5.5 based releases |
+---------------------------+--------------------------------------+-------------------------------------+
| | List of nodes to be waited for. | |
| --wait-nodes=list, | | All MySQL 5.5 based releases |
| | | |
| -w | | |
+---------------------------+--------------------------------------+-------------------------------------+
Usage
ndb_waiter [-c connect_string]
Additional Options
o --no-contact, -n
Instead of waiting for the STARTED state, ndb_waiter continues running until the cluster reaches NO_CONTACT status before exiting.
o --not-started
Instead of waiting for the STARTED state, ndb_waiter continues running until the cluster reaches NOT_STARTED status before exiting.
o --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).
o --single-user
The program waits for the cluster to enter single user mode.
o --nowait-nodes=list
When this option is used, ndb_waiter does not wait for the nodes whose IDs are listed. The list is comma-delimited; ranges can be
indicated by dashes, as shown here:
shell> ndb_waiter --nowait-nodes=1,3,7-9
Important
Do not use this option together with the --wait-nodes option.
o --wait-nodes=list, -w list
When this option is used, ndb_waiter waits only for the nodes whose IDs are listed. The list is comma-delimited; ranges can be
indicated by dashes, as shown here:
shell> ndb_waiter --wait-nodes=2,4-6,10
Important
Do not use this option together with the --nowait-nodes option.
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 connection string is specified, then ndb_waiter tries to connect to a management on localhost, and reports Connecting to mgmsrv
at (null).
COPYRIGHT
Copyright (C) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
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
Oracle Corporation (http://dev.mysql.com/).
MySQL 5.5 01/30/2014 NDB_WAITER(1)