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The order in which the group’s children (sub groups and cartridges) need to started up.

If it is a group, it should use the format of "group.<GROUP_ALIAS>" and if it is a cartridge, it should be "cartridge.<CARTRIDGE_ALIAS>" when defining startupOrder. Multiple startupOrders can also be defined as String array. However, the startupOrder should not create a cyclic dependency. By defining multiple startupOrders, parallel dependencies can be identified to start them in parallel.

• If the startupOrder is as follows, group3, group1 should come before tomcat and php. However, tomcat or php can come up in any order.

  Code Block
  "startupOrders": [ { "aliases": [ "group.group3", "cartridge.tomcat" ] }, { "aliases": [ "group.group1", "cartridge.php" ] } ],

• If the startupOrder is as follows, then group1 will come up first, then tomcat and then php.

  Code Block
  "startupOrders": [ { "aliases":[  "group.group1", "cartridge.tomcat", "cartridge.php" ] } ],

• If the startupOrder has two independent rules defined as follows, then once group1 is brought up, tomcat and php can be brought up in parallel.

  Code Block
  "startupOrders": [ { "aliases": [ "group.group1", "cartridge.tomcat" ] }, { "aliases": [ "group.group1", "cartridge.php" ] } ],

• If a startupOrder is not defined then the groups or cartridges will be started up parallel to each other.

This determines how the instances need to be terminated. The following is the example startupOrder used to explain the terminationBehaviour:

"startupOrders": [
  {
    "aliases": [
      "group.group1",
      "cartridge.tomcat"
    ]
  },
  {
    "aliases": [
      "group.group1",
      "cartridge.php"
    ]
  }
],

The available terminationBehaviours are as follows:

• terminate-none
None of the children in a group will be terminated. For example, if something happens to group1, it will not have an impact on tomcat or php.
• terminate-all
  All the elements in that dependency tree will be terminated. For example, if something happens to php, then all the children of the group that php belongs to, will be get terminated regardless of the other dependency information. Note that cartridges and sub-groups are considered as the children of a group.
• terminate-dependents
  Only the dependents will be terminated.
  For example:
  
  • If something happens to group1, then tomcat and php will get terminated. However, if any other cartridge or group is found in the parent group that group1 belongs to, then that cartridge or group will remain as it is in WSO2 Private PaaS.
  • If something happens to php, nothing will get terminated as php does not have any dependancies.

scalingDependents

Defines if there are any dependencies with regard to scaling. When dependent scaling is defined among members (cartridge or a group), and scaling (scaling up or down) is taking place for any of the members, all other dependent members will also scale in order to maintain the defined ratio.

scalingDependents array 

group.group1,
cartridge.tomcat