Product SiteDocumentation Site

2.6. Realizând Modificări de Configurare într-un Sandbox

Often it is desirable to preview the effects of a series of changes before updating the configuration atomically. For this purpose we have created crm_shadow which creates a "shadow" copy of the configuration and arranges for all the command line tools to use it.
To begin, simply invoke crm_shadow and give it the name of a configuration to create [5] ; be sure to follow the simple on-screen instructions.

Avertisment

Read the above carefully, failure to do so could result in you destroying the cluster’s active configuration!

Exemplu 2.7. Crearea şi prezentarea sandbox-ului activ

 # crm_shadow --create test
 Setting up shadow instance
 Type Ctrl-D to exit the crm_shadow shell
 shadow[test]:
 shadow[test] # crm_shadow --which
 test

From this point on, all cluster commands will automatically use the shadow copy instead of talking to the cluster’s active configuration. Once you have finished experimenting, you can either commit the changes, or discard them as shown below. Again, be sure to follow the on-screen instructions carefully.
For a full list of crm_shadow options and commands, invoke it with the <parameter>--help</parameter> option.

Exemplu 2.8. Folosirea unui sandbox pentru a realiza mai multe modificări în mod atomic

 shadow[test] # crm_failcount -G -r rsc_c001n01
  name=fail-count-rsc_c001n01 value=0
 shadow[test] # crm_standby -v on -n c001n02
 shadow[test] # crm_standby -G -n c001n02
 name=c001n02 scope=nodes value=on
 shadow[test] # cibadmin --erase --force
 shadow[test] # cibadmin --query
 <cib cib_feature_revision="1" validate-with="pacemaker-1.0" admin_epoch="0" crm_feature_set="3.0" have-quorum="1" epoch="112"
      dc-uuid="c001n01" num_updates="1" cib-last-written="Fri Jun 27 12:17:10 2008">
    <configuration>
       <crm_config/>
       <nodes/>
       <resources/>
       <constraints/>
    </configuration>
    <status/>
 </cib>
  shadow[test] # crm_shadow --delete test --force
  Now type Ctrl-D to exit the crm_shadow shell
  shadow[test] # exit
  # crm_shadow --which
  No shadow instance provided
  # cibadmin -Q
 <cib cib_feature_revision="1" validate-with="pacemaker-1.0" admin_epoch="0" crm_feature_set="3.0" have-quorum="1" epoch="110"
       dc-uuid="c001n01" num_updates="551">
    <configuration>
       <crm_config>
          <cluster_property_set id="cib-bootstrap-options">
             <nvpair id="cib-bootstrap-1" name="stonith-enabled" value="1"/>
             <nvpair id="cib-bootstrap-2" name="pe-input-series-max" value="30000"/>

Realizarea de modificări într-un sandbox şi apoi verificarea că, configuraţia reală nu este atinsă.


[5] Shadow copies are identified with a name, making it possible to have more than one.