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processors either ignore nonessential whitespace as a matter of course, or can be instructed to do so. 

The XML output also indicates when changing a given parameter requires that data nodes be restarted using the --initial  option. This is shown by the presence of an initial="true"  attribute in the corresponding <param>  element. In addition, the restart type ( system  or node ) is also shown; if a given parameter requires a system restart, this is indicated by the presence of a restart="system" attribute in the corresponding <param>  element. For example, changing the value set for the Diskless parameter requires a system initial restart, as shown here (with the restart  and initial  attributes highlighted for visibility): 

<param name="Diskless" comment="Run wo/ disk" type="bool" default="false" restart="system" initial="true" /> 

Currently, no initial  attribute is included in the XML output for <param>  elements corresponding to parameters which do not require initial restarts; in other words, initial="false"  is the default, and the value false  should be assumed if the attribute is not present. Similarly, the default restart type is node  (that is, an online or “rolling”  restart of the cluster), but the restart  attribute is included only if the restart type is system  (meaning that all cluster nodes must be shut down at the same time, then restarted). 

Deprecated parameters are indicated in the XML output by the deprecated  attribute, as shown here: 

<param name="NoOfDiskPagesToDiskAfterRestartACC" comment="DiskCheckpointSpeed" type="unsigned" default="20" min="1" max="4294967039" deprecated="true" /> 

In such cases, the comment  refers to one or more parameters that supersede the deprecated parameter. Similarly to initial , the deprecated  attribute is indicated only when the parameter is deprecated, with deprecated="true" , and does not appear at all for parameters which are not deprecated. (Bug #21127135) 

Parameters that are required are indicated with mandatory="true" , as shown here: 

<param name="NodeId" comment="Number identifying application node (mysqld(API))" type="unsigned" mandatory="true"  min="1" max="255"/> 

In much the same way that the initial  or deprecated  attribute is displayed only for a parameter that requires an intial restart or that is deprecated, the mandatory  attribute is included only if the given parameter is actually required. 

<img src='content_image/679452.jpg'>

## Important 

The --xml  option can be used only with the --configinfo  option. Using -- xml  without --configinfo  fails with an error. 

Unlike the options used with this program to obtain current configuration data, --configinfo  and -- xml  use information obtained from the NDB Cluster sources when ndb_config  was compiled. For this reason, no connection to a running NDB Cluster or access to a config.ini  or my.cnf  file is required for these two options. 

• --print-defaults 

<img src='content_image/679450.jpg'>

Print program argument list and exit. 

• --defaults-file 

