Reorder Elements In Configuration Data Using the Junos XML Protocol

For most configuration objects, the order in which the object or its children are created is not significant, because the Junos OS configuration management software stores and displays configuration objects in predetermined positions in the configuration hierarchy. However, some configuration objects—such as routing policies and firewall filters—consist of elements that must be processed and analyzed sequentially in order to produce the intended routing behavior. When a client application uses the Junos XML management protocol to add a new element to an ordered set, the element is appended to the existing list of elements. The client application can then reorder the elements, if appropriate.

In a Junos XML protocol session with a device running Junos OS, to change the order of configuration elements in an ordered set, a client application first includes the tag elements described in Creating, Modifying, or Deleting Configuration Elements Using the Junos XML Protocol. If using Junos XML tag elements, the application emits the container tag element that represents the ordered set, and encloses the tag element for each identifier of the configuration element that is moving. In the following examples, the identifier tag element is called <name>.

To move an existing element to the first position in an ordered set, the application includes the insert="first" attribute in the opening container tag for that element.

<configuration>
    <!-- opening tag for each parent of the set -->
        <ordered-set insert="first"> 
            <name>identifier-for-moving-object</name> 
        </ordered-set> 
    <!-- closing tag for each parent of the set -->
</configuration>

To move an existing element to a position that is relative to another element, the application includes the insert="before" or insert="after" attribute in the opening container tag to indicate the new position of the moving element relative to another reference element in the set. To identify the reference element, it includes each of the reference element’s identifiers as an attribute in the opening container tag for the ordered set.

In the following example, the elements in the set have one identifier, called <name>:

<configuration>
    <!-- opening tag for each parent of the set -->
        <ordered-set insert="(before | after)" name="referent-value"> 
            <name>identifier-for-moving-object</name> 
        </ordered-set> 
    <!-- closing tag for each parent of the set -->
</configuration>

In the following example, each element in the set has two identifiers. The opening tag appears on two lines for legibility only:

<configuration>
    <!-- opening tag for each parent of the set -->
        <ordered-set insert="(before | after)" identifier1="referent-value"
                    identifier2="referent-value"> 
            <identifier1>value-for-moving-object</identifier1> 
            <identifier2>value-for-moving-object</identifier2> 
        </ordered-set> 
    <!-- closing tag for each parent of the set -->
</configuration>

The insert attribute can be combined with the inactive or active attribute to deactivate or reactivate the configuration element as it is reordered. For more information, see Changing a Configuration Element’s Activation State Simultaneously with Other Changes Using the Junos XML Protocol.

When using configuration mode commands to reorder elements, the application specifies the insert command that is equivalent to the CLI configuration mode command.

<configuration-set>
    insert statement-path-to-object identifier-for-moving-object (before | after) referent-value 
</configuration-set>

The following example shows how to move a firewall filter called older-filter, defined at the [edit firewall filter] hierarchy level, and place it after another filter called newer-filter using Junos XML tag elements. This operation is equivalent to the following configuration mode command:

[edit]
user@host# insert firewall family inet filter older-filter after filter newer-filter 

The following example shows how to move a firewall filter called older-filter, defined at the [edit firewall filter] hierarchy level, and place it after another filter called newer-filter using configuration mode commands:

<rpc>
    <load-configuration action="set" format="text">
        <configuration-set>
            insert firewall family inet filter older-filter after filter newer-filter 
        </configuration-set>
    </load-configuration>
</rpc>

The following example shows how to move an OSPF virtual link defined at the [edit protocols ospf area area] hierarchy level. The link with identifiers neighbor-id 192.168.0.3 and transit-area 10.10.10.1 moves before the link with identifiers neighbor-id 192.168.0.5 and transit-area 10.10.10.2. This operation is equivalent to the following configuration mode command:

[edit protocols ospf area area]
user@host# insert virtual-link neighbor-id 192.168.0.3 transit-area 10.10.10.1 before virtual-link neighbor-id 192.168.0.5 transit-area 10.10.10.2 

Client Application

<rpc>
<load-configuration>
    <configuration>
        <protocols>
            <ospf>
                <area>
                    <name>area</name>
                    <virtual-link insert="before" neighbor-id="192.168.0.5" transit-area="10.10.10.2">
                        <neighbor-id>192.168.0.3</neighbor-id>
                        <transit-area>10.10.10.1</transit-area>
                    </virtual-link>
                </area>
            </ospf>
        </protocols>
    </configuration>
</load-configuration>
</rpc>

Junos XML Protocol Server

<rpc-reply xmlns:junos="URL">
   <load-configuration-results>
      <load-success/>
   </load-configuration-results>
</rpc-reply>