25.5.30 ndb_waiter — Wait for NDB Cluster to Reach a Given Status

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 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.

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
`--character-sets-dir=path`	Directory containing character sets	REMOVED: 8.0.31
`--connect-retries=#`	Number of times to retry connection before giving up	(Supported in all NDB releases based on MySQL 8.0)
`--connect-retry-delay=#`	Number of seconds to wait between attempts to contact management server	(Supported in all NDB releases based on MySQL 8.0)
`--connect-string=connection_string`, `-c connection_string`	Same as --ndb-connectstring	(Supported in all NDB releases based on MySQL 8.0)
`--core-file`	Write core file on error; used in debugging	REMOVED: 8.0.31
`--defaults-extra-file=path`	Read given file after global files are read	(Supported in all NDB releases based on MySQL 8.0)
`--defaults-file=path`	Read default options from given file only	(Supported in all NDB releases based on MySQL 8.0)
`--defaults-group-suffix=string`	Also read groups with concat(group, suffix)	(Supported in all NDB releases based on MySQL 8.0)
`--help`, `-?`	Display help text and exit	(Supported in all NDB releases based on MySQL 8.0)
`--login-path=path`	Read given path from login file	(Supported in all NDB releases based on MySQL 8.0)
`--ndb-connectstring=connection_string`, `-c connection_string`	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 8.0)
`--ndb-mgmd-host=connection_string`, `-c connection_string`	Same as --ndb-connectstring	(Supported in all NDB releases based on MySQL 8.0)
`--ndb-nodeid=#`	Set node ID for this node, overriding any ID set by --ndb-connectstring	REMOVED: 8.0.31
`--ndb-optimized-node-selection`	Enable optimizations for selection of nodes for transactions. Enabled by default; use --skip-ndb-optimized-node-selection to disable	REMOVED: 8.0.31
`--no-contact`, `-n`	Wait for cluster to reach NO CONTACT state	(Supported in all NDB releases based on MySQL 8.0)
`--no-defaults`	Do not read default options from any option file other than login file	(Supported in all NDB releases based on MySQL 8.0)
`--not-started`	Wait for cluster to reach NOT STARTED state	(Supported in all NDB releases based on MySQL 8.0)
`--nowait-nodes=list`	List of nodes not to be waited for	(Supported in all NDB releases based on MySQL 8.0)
`--print-defaults`	Print program argument list and exit	(Supported in all NDB releases based on MySQL 8.0)
`--single-user`	Wait for cluster to enter single user mode	(Supported in all NDB releases based on MySQL 8.0)
`--timeout=#`, `-t #`	Wait this many seconds, then exit whether or not cluster has reached desired state	(Supported in all NDB releases based on MySQL 8.0)
`--usage`, `-?`	Display help text and exit; same as --help	(Supported in all NDB releases based on MySQL 8.0)
`--verbose=#`, `-v`	Set output verbosity level; see text for input and return values	ADDED: 8.0.37
`--version`, `-V`	Display version information and exit	(Supported in all NDB releases based on MySQL 8.0)
`--wait-nodes=list`, `-w list`	List of nodes to be waited for	(Supported in all NDB releases based on MySQL 8.0)

Usage

ndb_waiter [-c connection_string]

Additional Options

--character-sets-dir
Command-Line Format --character-sets-dir=path
Removed 8.0.31
Directory containing character sets.
--connect-retries
Command-Line Format --connect-retries=#
Type Integer
Default Value 12
Minimum Value 0
Maximum Value 12
Number of times to retry connection before giving up.
--connect-retry-delay
Command-Line Format --connect-retry-delay=#
Type Integer
Default Value 5
Minimum Value 0
Maximum Value 5
Number of seconds to wait between attempts to contact management server.
--connect-string
Command-Line Format --connect-string=connection_string
Type String
Default Value [none]
Same as --ndb-connectstring.
--core-file
Command-Line Format --core-file
Removed 8.0.31
Write core file on error; used in debugging.
--defaults-extra-file
Command-Line Format --defaults-extra-file=path
Type String
Default Value [none]
Read given file after global files are read.
--defaults-file
Command-Line Format --defaults-file=path
Type String
Default Value [none]
Read default options from given file only.
--defaults-group-suffix
Command-Line Format --defaults-group-suffix=string
Type String
Default Value [none]
Also read groups with concat(group, suffix).
--login-path
Command-Line Format --login-path=path
Type String
Default Value [none]
Read given path from login file.
--help
Command-Line Format --help
Display help text and exit.
--ndb-connectstring
Command-Line Format --ndb-connectstring=connection_string
Type String
Default Value [none]
Set connect string for connecting to ndb_mgmd. Syntax: "[nodeid=id;][host=]hostname[:port]". Overrides entries in NDB_CONNECTSTRING and my.cnf.
--ndb-mgmd-host
Command-Line Format --ndb-mgmd-host=connection_string
Type String
Default Value [none]
Same as --ndb-connectstring.
--ndb-nodeid
Command-Line Format --ndb-nodeid=#
Removed 8.0.31
Type Integer
Default Value [none]
Set node ID for this node, overriding any ID set by --ndb-connectstring.
--ndb-optimized-node-selection
Command-Line Format --ndb-optimized-node-selection
Removed 8.0.31
Enable optimizations for selection of nodes for transactions. Enabled by default; use --skip-ndb-optimized-node-selection to disable.
--no-contact, -n
Instead of waiting for the STARTED state, ndb_waiter continues running until the cluster reaches NO_CONTACT status before exiting.
--no-defaults
Command-Line Format --no-defaults
Do not read default options from any option file other than login file.
--not-started
Instead of waiting for the STARTED state, ndb_waiter continues running until the cluster reaches NOT_STARTED status before exiting.
--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:
```
$> ndb_waiter --nowait-nodes=1,3,7-9
```
Important
Do not use this option together with the --wait-nodes option.
--print-defaults
Command-Line Format --print-defaults
Print program argument list and exit.
--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).
--single-user
The program waits for the cluster to enter single user mode.
--usage
Command-Line Format --usage
Display help text and exit; same as --help.
--verbose
Command-Line Format --verbose=#
Introduced 8.0.37
Type Integer
Default Value 2
Minimum Value 0
Maximum Value 2
Controls verbosity level of printout. Possible levels and their effects are listed here:
- 0: Do not print (return exit code only; see following for exit codes).
- 1: Print final connection status only.
- 2: Print status each time it is checked.
  This is the same behavior as in versions of NDB Cluster previous to 8.4.
Exit codes returned by ndb_waiter are listed here, with their meanings:
- 0: Success.
- 1: Wait timed out.
- 2: Parameter error, such as an invalid node ID.
- 3: Failed to connect to the management server.
--version
Command-Line Format --version
Display version information and exit.
--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:
```
$> ndb_waiter --wait-nodes=2,4-6,10
```
Important
Do not use this option together with the --nowait-nodes option.

Command-Line Format	`--character-sets-dir=path`
Removed	8.0.31

Command-Line Format	`--connect-retries=#`
Type	Integer
Default Value	`12`
Minimum Value	`0`
Maximum Value	`12`

Command-Line Format	`--connect-retry-delay=#`
Type	Integer
Default Value	`5`
Minimum Value	`0`
Maximum Value	`5`

Command-Line Format	`--connect-string=connection_string`
Type	String
Default Value	`[none]`

Command-Line Format	`--core-file`
Removed	8.0.31

Command-Line Format	`--defaults-extra-file=path`
Type	String
Default Value	`[none]`

Command-Line Format	`--defaults-file=path`
Type	String
Default Value	`[none]`

Command-Line Format	`--defaults-group-suffix=string`
Type	String
Default Value	`[none]`

Command-Line Format	`--login-path=path`
Type	String
Default Value	`[none]`

Command-Line Format	`--help`

Command-Line Format	`--ndb-connectstring=connection_string`
Type	String
Default Value	`[none]`

Command-Line Format	`--ndb-mgmd-host=connection_string`
Type	String
Default Value	`[none]`

Command-Line Format	`--ndb-nodeid=#`
Removed	8.0.31
Type	Integer
Default Value	`[none]`

Command-Line Format	`--ndb-optimized-node-selection`
Removed	8.0.31

Command-Line Format	`--no-defaults`

Command-Line Format	`--print-defaults`

Command-Line Format	`--usage`

Command-Line Format	`--verbose=#`
Introduced	8.0.37
Type	Integer
Default Value	`2`
Minimum Value	`0`
Maximum Value	`2`

Command-Line Format	`--version`

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

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).

Prior to NDB 8.0.20, this program printed NDBT_ProgramExit - status upon completion of its run, due to an unnecessary dependency on the NDBT testing library. This dependency has been removed, eliminating the extraneous output.