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:
-
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 aSTARTorRESTARTcommand 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'sRESTARTcommand. -
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.
Options that can be used with ndb_waiter are shown in the following table. Additional descriptions follow the table.
Table 25.51 Command-line options used with the program ndb_waiter
| Format | Description | Added, Deprecated, or Removed |
|---|---|---|
| Number of times to retry connection before giving up |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Number of seconds to wait between attempts to contact management server |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Same as --ndb-connectstring |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Read given file after global files are read |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Read default options from given file only |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Also read groups with concat(group, suffix) |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Display help text and exit |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Read given path from login file |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Do not read login paths from the login path file |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Set connect string for connecting to ndb_mgmd. Syntax: "[nodeid=id;][host=]hostname[:port]". Overrides entries in NDB_CONNECTSTRING and my.cnf |
(Supported in all NDB releases based on MySQL 8.3) |
|
| ndb_mgm client TLS requirement level |
ADDED: 8.3.0 |
|
| Same as --ndb-connectstring |
(Supported in all NDB releases based on MySQL 8.3) |
|
| List of directories containing TLS keys and certificates |
ADDED: 8.3.0 |
|
| Wait for cluster to reach NO CONTACT state |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Do not read default options from any option file other than login file |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Wait for cluster to reach NOT STARTED state |
(Supported in all NDB releases based on MySQL 8.3) |
|
| List of nodes not to be waited for |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Print program argument list and exit |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Wait for cluster to enter single user mode |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Wait this many seconds, then exit whether or not cluster has reached desired state |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Display help text and exit; same as --help |
(Supported in all NDB releases based on MySQL 8.3) |
|
| Display version information and exit |
(Supported in all NDB releases based on MySQL 8.3) |
|
| List of nodes to be waited for |
(Supported in all NDB releases based on MySQL 8.3) |
Usage
ndb_waiter [-c connection_string]
Additional Options
-
Command-Line Format --character-sets-dir=pathDirectory containing character sets.
-
Command-Line Format --connect-retries=#Type Integer Default Value 12Minimum Value 0Maximum Value 12Number of times to retry connection before giving up.
-
Command-Line Format --connect-retry-delay=#Type Integer Default Value 5Minimum Value 0Maximum Value 5Number of seconds to wait between attempts to contact management server.
-
Command-Line Format --connect-string=connection_stringType String Default Value [none]Same as
--ndb-connectstring. -
Command-Line Format --core-fileWrite core file on error; used in debugging.
-
Command-Line Format --defaults-extra-file=pathType String Default Value [none]Read given file after global files are read.
-
Command-Line Format --defaults-file=pathType String Default Value [none]Read default options from given file only.
-
Command-Line Format --defaults-group-suffix=stringType String Default Value [none]Also read groups with concat(group, suffix).
-
Command-Line Format --login-path=pathType String Default Value [none]Read given path from login file.
-
Command-Line Format --no-login-pathsSkips reading options from the login path file.
-
Command-Line Format --helpDisplay help text and exit.
-
Command-Line Format --ndb-connectstring=connection_stringType String Default Value [none]Set connection string for connecting to ndb_mgmd. Syntax:
[nodeid=. Overrides entries inid;][host=]hostname[:port]NDB_CONNECTSTRINGandmy.cnf. -
Command-Line Format --ndb-mgm-tls=levelType Enumeration Default Value relaxedValid Values relaxedstrictSets the level of TLS support required to connect to the management server; one of
relaxedorstrict.relaxed(the default) means that a TLS connection is attempted, but success is not required;strictmeans that TLS is required to connect. -
Command-Line Format --ndb-mgmd-host=connection_stringType String Default Value [none]Same as --
ndb-connectstring. -
Command-Line Format --ndb-nodeid=#Type Integer Default Value [none]Set node ID for this node, overriding any ID set by
--ndb-connectstring. -
--ndb-optimized-node-selectionCommand-Line Format --ndb-optimized-node-selectionEnable optimizations for selection of nodes for transactions. Enabled by default; use
--skip-ndb-optimized-node-selectionto disable. -
Command-Line Format --ndb-tls-search-path=listType Path name Default Value (Unix) $HOME/ndb-tlsDefault Value (Windows) $HOMEDIR/ndb-tlsSpecify a list of directories to search for a CA file. On Unix platforms, the directory names are separated by colons (
:); on Windows systems, the semicolon character (;) is used as the separator. A directory reference may be relative or absolute; it may contain one or more environment variables, each denoted by a prefixed dollar sign ($), and expanded prior to use.Searching begins with the leftmost named directory and proceeds from left to right until a file is found. An empty string denotes an empty search path, which causes all searches to fail. A string consisting of a single dot (
.) indicates that the search path limited to the current working directory.If no search path is supplied, the compiled-in default value is used. This value depends on the platform used: On Windows, this is
\ndb-tls; on other platforms (including Linux), it is$HOME/ndb-tls. This can be overridden by compiling NDB Cluster using-DWITH_NDB_TLS_SEARCH_PATH. -
--no-contact,-nInstead of waiting for the
STARTEDstate, ndb_waiter continues running until the cluster reachesNO_CONTACTstatus before exiting. -
Command-Line Format --no-defaultsDo not read default options from any option file other than login file.
-
Instead of waiting for the
STARTEDstate, ndb_waiter continues running until the cluster reachesNOT_STARTEDstatus before exiting. -
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:
$> ndb_waiter --nowait-nodes=1,3,7-9ImportantDo not use this option together with the
--wait-nodesoption. -
Command-Line Format --print-defaultsPrint program argument list and exit.
-
--timeout=,seconds-tsecondsTime 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).
-
The program waits for the cluster to enter single user mode.
-
Command-Line Format --usageDisplay help text and exit; same as
--help. -
Command-Line Format --versionDisplay version information and exit.
-
--wait-nodes=,list-wlistWhen 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:
$> ndb_waiter --wait-nodes=2,4-6,10ImportantDo not use this option together with the
--nowait-nodesoption.
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.
$> ./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
If no connection string is specified, then ndb_waiter tries to connect to a management on localhost, and reports Connecting to mgmsrv at (null).