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Table of Contents Expand all

play_arrow Overview
- play_arrow Junos Automation Scripts Overview
- play_arrow Junos XML Management Protocol and Junos XML API Overview
play_arrow Automation Scripting Using XSLT
- play_arrow XSLT Overview
- play_arrow Standard XPath and XSLT Functions Used in Automation Scripts
- play_arrow Standard XSLT Elements and Attributes Used in Automation Scripts
play_arrow Automation Scripting Using SLAX
- play_arrow SLAX Overview
- play_arrow SLAX Statements
- play_arrow The libslax Distribution for Automation Scripting
play_arrow Automation Scripting Using Python
- play_arrow Python Overview
play_arrow Automation Script Input
- play_arrow Global Parameters in Automation Scripts
  - Global Parameters and Variables in Junos OS Automation Scripts
play_arrow Extension Functions and Named Templates for Automation Scripts
play_arrow Manage Automation Scripts
- play_arrow Store and Enable Scripts
- play_arrow Configure a Remote Source for Scripts
- play_arrow Configure the Session Protocol for Scripts
  - Understanding the Session Protocol in Automation Scripts
  - Example: Specify the Session Protocol for a Connection within Scripts
- play_arrow Control Execution of Scripts
- play_arrow Synchronize Scripts Between Routing Engines
- play_arrow Convert Scripts Between SLAX and XSLT
  - Convert Scripts Between SLAX and XSLT
play_arrow Commit Scripts
- play_arrow Commit Scripts Overview
  - Commit Script Overview
  - How Commit Scripts Work
- play_arrow Create and Execute Commit Scripts
- play_arrow Generate a Custom Warning, Error, or System Log Message Using Commit Scripts
- play_arrow Generate Persistent or Transient Configuration Changes Using Commit Scripts
- play_arrow Create Custom Configuration Syntax with Commit Script Macros
- play_arrow Commit Script Examples
- play_arrow Junos XML and XSLT Tag Elements Used in Commit Scripts
- play_arrow Troubleshoot Commit Scripts
play_arrow Op Scripts
- play_arrow Op Scripts Overview
  - Op Script Overview
  - How Op Scripts Work
- play_arrow Create and Execute Op Scripts
- play_arrow Op Script Examples
- play_arrow Provision Services Using Service Template Automation
  - Service Template Automation Overview
  - Example: Configure Service Template Automation
- play_arrow Troubleshoot Op Scripts
  - Trace Op Script Processing on Devices Running Junos OS
  - Trace Script Processing on Devices Running Junos OS Evolved
play_arrow Event Policies and Event Scripts
play_arrow SNMP Scripts
- play_arrow SNMP Scripts Overview
  - SNMP Scripts Overview
- play_arrow Create and Execute SNMP Scripts
- play_arrow SNMP Script Example
  - Example: Process Unsupported OIDs with an SNMP Script
- play_arrow Troubleshoot SNMP Scripts
  - Trace SNMP Script Processing on Devices Running Junos OS
  - Trace Script Processing on Devices Running Junos OS Evolved
play_arrow Configuration Statements and Operational Commands
- Junos CLI Reference Overview

list Table of Contents

English

Example: Generate Persistent and Transient Configuration Changes Using Commit Scripts

date_range 16-Feb-24

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Example: Generating a Persistent Change

Junos OS commit scripts enable users to customize the validation process of their configurations in accordance with their own practices and policies and enforce custom configuration rules during the commit process. This example demonstrates a commit script that generates a persistent change that adds the family mpls statement in the configuration of SONET/SDH interfaces when the statement is not already included in the configuration. If you do not explicitly configure the MPLS protocol family on an interface, the interface is not enabled for MPLS applications.

Requirements
Overview and Commit Script
Configuration
Verification

Requirements

This example uses the following hardware and software components:

Device running Junos OS with one or more SONET/SDH interfaces.
Junos OS Release 16.1R3 or later release when using a Python script.

Overview and Commit Script

The commit script in this example finds all SONET/SDH interfaces that have a logical interface configured but that do not have the family mpls statement configured. For these interfaces, the script adds the family mpls statement to the interface configuration as a persistent change at the [edit interfaces interface-name unit logical-unit-number] hierarchy level. The script is shown in SLAX, XSLT, and Python.

The SLAX and XSLT versions of the commit script generate the persistent change by using the jcs:emit-change template, which is a helper template contained in the junos.xsl import file. The tag parameter of the jcs:emit-change template is omitted, which directs the script to emit the change as a persistent change. The content parameter of the jcs:emit-change template includes the configuration statements to add as a persistent change. The message parameter of the jcs:emit-change template includes the warning message to be displayed in the CLI, notifying you that the configuration has been changed.

The Python version of the commit script generates the persistent change by using the jcs.emit_change() function, which is imported from the jcs module. The Python script indicates that this is a persistent change by passing in the positional argument 'change'.

XSLT Syntax

content_copy zoom_out_map
<?xml version="1.0" standalone="yes"?>
<xsl:stylesheet version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
    xmlns:junos="http://xml.juniper.net/junos/*/junos" 
    xmlns:xnm="http://xml.juniper.net/xnm/1.1/xnm" 
    xmlns:jcs="http://xml.juniper.net/junos/commit-scripts/1.0">
    <xsl:import href="../import/junos.xsl"/>
 
    <xsl:template match="configuration">
        <xsl:for-each select="interfaces/interface[starts-with(name, 'so-')]/unit">
            <xsl:if test="not(family/mpls)">
                <xsl:call-template name="jcs:emit-change">
                    <xsl:with-param name="message">
                        <xsl:text>Adding 'family mpls' to SONET/SDH interface.</xsl:text>
                    </xsl:with-param>
                    <xsl:with-param name="content">
                            <family>
                                <mpls/>
                            </family>
                    </xsl:with-param>
                </xsl:call-template>
            </xsl:if>
        </xsl:for-each>
    </xsl:template>
</xsl:stylesheet>

SLAX Syntax

content_copy zoom_out_map
version 1.0;
ns junos = "http://xml.juniper.net/junos/*/junos";
ns xnm = "http://xml.juniper.net/xnm/1.1/xnm";
ns jcs = "http://xml.juniper.net/junos/commit-scripts/1.0";
import "../import/junos.xsl";
 
match configuration {
    for-each (interfaces/interface[starts-with(name, 'so-')]/unit) {
        if (not(family/mpls)) {
            call jcs:emit-change() {
                with $message = {
                    expr "Adding 'family mpls' to SONET/SDH interface.";
                }
                with $content = {
                    <family> {
                        <mpls>;
                    }
                }
            }
        }
    }
}

Python Syntax

content_copy zoom_out_map
from junos import Junos_Configuration
import jcs

def main():
    # Get configuration root object
    root = Junos_Configuration

    for element in root.xpath("./interfaces/ \
        interface[starts-with(name,'so-')]/unit"):
        if element.find('family/mpls') is None:
            if_name = element.find('../name').text
            unit_name = element.find('name').text
            change_xml = """
            <interfaces>
               <interface>
                  <name>{0}</name>
                  <unit>
                     <name>{1}</name>
                     <family>
                        <mpls>
                        </mpls>
                     </family>
                  </unit>
               </interface>
            </interfaces>
            """.format(if_name, unit_name).strip()
            jcs.emit_change(change_xml, "change", "xml")
            jcs.emit_warning("Adding 'family mpls' to SONET/SDH interface: " + if_name)

if __name__ == '__main__':
    main()

Configuration

Procedure

Step-by-Step Procedure

To download, enable, and test the script.

Copy the script into a text file, name the file mpls.xsl, mpls.slax, or mpls.py as appropriate, and copy it to the /var/db/scripts/commit/ directory on the device.

Note:
Unsigned Python scripts must be owned by either root or a user in the Junos OS super-user login class, and only the file owner can have write permission for the file.
In configuration mode, configure the file statement and the script filename at the [edit system scripts commit] hierarchy level.
```
[edit]
user@host# set system scripts commit file mpls.xsl
```
If the script is written in Python, enable the execution of unsigned Python scripts.
```
[edit]
user@host# set system scripts language python
```
Note:
Configure the language python3 statement to use Python 3 to execute Python scripts, or configure the language python statement to use Python 2.7 to execute Python scripts. For more information, see language.
To test that the commit script generates the persistent change correctly, make sure that the configuration contains the condition that elicits the change. To test this script, ensure that the family mpls statement is not included at the [edit interfaces so-fpc/pic/port unit logical-unit-number] hierarchy level for at least one SONET/SDH interface.
Issue the commit check command to preview a trace of commit script processing to verify that the script will add the persistent change to the candidate configuration. The commit check command verifies the syntax of the configuration prior to a commit, but it does not commit the changes.

The commit script in this example produces a message for each change it makes. Use the commit check command to preview these messages to determine whether the script will update the configuration with the family mpls statement for the appropriate interfaces.

Issue the commit check | display xml command to display the XML-formatted version of the message. The sample output indicates that the script will add the family mpls statement to the so-2/3/4.0 interface configuration during the commit operation.
```
[edit]
user@host# commit check | display xml
<rpc-reply xmlns:junos="http://xml.juniper.net/junos/11.2R1/junos">
    <commit-results>
        <routing-engine junos:style="normal">
            <name>re0</name>
            <xnm:warning xmlns:xnm="http://xml.juniper.net/xnm/1.1/xnm">
                <edit-path>
                    [edit interfaces interface so-2/3/4 unit 0]
                </edit-path>
                <message>
                    Adding 'family mpls' to SONET/SDH interface.
                </message>
            </xnm:warning>
            <commit-check-success/>
        </routing-engine>
    </commit-results>
</rpc-reply>
```

To display a detailed trace of commit script processing, issue the commit check | display detail command. In the sample output, there is one persistent change that will be loaded into the configuration during the commit operation.

content_copy zoom_out_map
[edit]
user@host# commit check | display detail
2011-06-17 14:17:35 PDT: reading commit script configuration
2011-06-17 14:17:35 PDT: testing commit script configuration
2011-06-17 14:17:35 PDT: opening commit script '/var/db/scripts/commit/mpls.xsl'
2011-06-17 14:17:35 PDT: reading commit script 'mpls.xsl'
2011-06-17 14:17:35 PDT: running commit script 'mpls.xsl'
2011-06-17 14:17:35 PDT: processing commit script 'mpls.xsl'
2011-06-17 14:17:35 PDT: no errors from mpls.xsl
2011-06-17 14:17:35 PDT: saving commit script changes for script mpls.xsl
2011-06-17 14:17:35 PDT: summary of script mpls.xsl: changes 1, transients 0, syslog 0
2011-06-17 14:17:35 PDT: start loading commit script changes
2011-06-17 14:17:35 PDT: loading commit script changes into real db
2011-06-17 14:17:35 PDT: finished commit script changes into real db
2011-06-17 14:17:35 PDT: no transient commit script changes
2011-06-17 14:17:35 PDT: finished loading commit script changes
2011-06-17 14:17:35 PDT: copying juniper.db to juniper.data+
2011-06-17 14:17:35 PDT: finished copying juniper.db to juniper.data+
...
configuration check succeeds

After verifying that the script produces the correct changes, issue the commit command to start the commit operation and execute the script.
```
user@host# commit
```

Verification

Purpose

Verify that the correct changes are integrated into the configuration.

Action

After executing the commit operation, view the configuration by issuing the show interfaces configuration mode command. If the MPLS protocol family is not enabled on one or more SONET/SDH interfaces before the script runs, the output is similar to the following:

content_copy zoom_out_map
[edit]
user@host# show interfaces
... other configured interface types ...
so-2/3/4 {
    unit 0 {
        family mpls; # Added by persistent change
    }
}
... other configured interface types ...

Example: Generating a Transient Change

This example uses a commit script to set PPP encapsulation on all SONET/SDH interfaces with the IPv4 protocol family enabled. The changes are added as transient changes.

Requirements
Overview and Commit Script
Configuration
Verification
Troubleshooting

Requirements

This example uses the following hardware and software components:

Device running Junos OS with one or more SONET/SDH interfaces.
Junos OS Release 16.1R3 or later release when using a Python script.

Overview and Commit Script

The commit script in this example finds all SONET/SDH interfaces with the IPv4 protocol family enabled in the configuration and adds the encapsulation ppp statement to the interface configuration. The commit script generates a transient change, which adds the change to the checkout configuration but not the candidate configuration. The script is shown in SLAX, XSLT, and Python.

The SLAX and XSLT versions of the commit script generate the transient change by using the jcs:emit-change template, which is a helper template contained in the junos.xsl import file. The tag parameter of the jcs:emit-change template has the value transient-change, which directs the script to emit the change as a transient change rather than a persistent change. The content parameter of the jcs:emit-change template includes the configuration statements to be added as a transient change.

The Python version of the commit script generates the transient change by using the jcs.emit_change() function, which is imported from the jcs module. The Python script indicates that this is a transient change by passing in the positional argument 'transient-change'.

XSLT Syntax

content_copy zoom_out_map
<?xml version="1.0" standalone="yes"?>
<xsl:stylesheet version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
    xmlns:junos="http://xml.juniper.net/junos/*/junos" 
    xmlns:xnm="http://xml.juniper.net/xnm/1.1/xnm" 
    xmlns:jcs="http://xml.juniper.net/junos/commit-scripts/1.0">
    <xsl:import href="../import/junos.xsl"/>
 
    <xsl:template match="configuration"> 
        <xsl:for-each select="interfaces/interface[starts-with(name, 'so-')
                          and unit/family/inet]">
            <xsl:call-template name="jcs:emit-change">
                <xsl:with-param name="tag" select="'transient-change'"/>
                <xsl:with-param name="content">
                    <encapsulation>ppp</encapsulation>
                </xsl:with-param>
            </xsl:call-template>
        </xsl:for-each> 
    </xsl:template> 
</xsl:stylesheet>

SLAX Syntax

content_copy zoom_out_map
version 1.0;
ns junos = "http://xml.juniper.net/junos/*/junos";
ns xnm = "http://xml.juniper.net/xnm/1.1/xnm";
ns jcs = "http://xml.juniper.net/junos/commit-scripts/1.0";
import "../import/junos.xsl";
 
match configuration {
    for-each (interfaces/interface[starts-with(name, 'so-') and unit/family/inet]) {
        call jcs:emit-change($tag = 'transient-change') {
            with $content = {
                <encapsulation> "ppp";
            }
        }
    }
}

Python Syntax

content_copy zoom_out_map
from junos import Junos_Configuration
import jcs

def main():
    # Get configuration root object
    root = Junos_Configuration

    for element in root.xpath("./interfaces/ \
        interface[starts-with(name,'so-') and unit/family/inet]"):
        if_name = element.find('name').text
        change_xml = """
        <interfaces>
           <interface>
              <name>{0}</name>
              <encapsulation>ppp</encapsulation>
           </interface>
        </interfaces>
        """.format(if_name).strip()
        jcs.emit_change(change_xml, "transient-change", "xml")
        jcs.emit_warning("Adding 'ppp' encapsulation to SONET interface: " + if_name)
        jcs.emit_warning(change_xml)

if __name__ == '__main__':
    main()

Configuration

Procedure

Step-by-Step Procedure

To download, enable, and test the script.

Copy the script into a text file, name the file encap-ppp.xsl, encap-ppp.slax, or encap-ppp.py as appropriate, and copy it to the /var/db/scripts/commit/ directory on the device.

Note:
Unsigned Python scripts must be owned by either root or a user in the Junos OS super-user login class, and only the file owner can have write permission for the file.
In configuration mode, configure the file statement and the script filename at the [edit system scripts commit] hierarchy level.
```
[edit]
user@host# set system scripts commit file encap-ppp.xsl
```
Configure the allow-transients statement to enable commit scripts to load transient changes into the checkout configuration.
```
[edit]
user@host# set system scripts commit allow-transients
```
If the script is written in Python, enable the execution of unsigned Python scripts.
```
[edit]
user@host# set system scripts language python3
```
Note:
Configure the language python3 statement to use Python 3 to execute Python scripts, or configure the language python statement to use Python 2.7 to execute Python scripts. For more information, see language.
To test that the commit script generates the transient change correctly, make sure that the configuration contains the condition that elicits the change. Ensure that the encapsulation ppp statement is not included at the [edit interfaces so-fpc/pic/port] hierarchy level for at least one SONET/SDH interface.

Issue the commit check command to preview a trace of commit script processing to verify that the script will add the transient change to the checkout configuration. The commit check command verifies the syntax of the configuration prior to a commit, but it does not commit the changes.

Issue the commit check | display detail command to display a detailed trace of commit script processing. In the sample output, there are two transient changes that are loaded into the checkout configuration.

content_copy zoom_out_map
[edit]
user@host# commit check | display detail
2011-06-15 12:07:30 PDT: reading commit script configuration
2011-06-15 12:07:30 PDT: testing commit script configuration
2011-06-15 12:07:30 PDT: opening commit script '/var/db/scripts/commit/encap-ppp.xsl'
2011-06-15 12:07:30 PDT: reading commit script 'encap-ppp.xsl'
2011-06-15 12:07:30 PDT: running commit script 'encap-ppp.xsl'
2011-06-15 12:07:30 PDT: processing commit script 'encap-ppp.xsl'
2011-06-15 12:07:30 PDT: no errors from encap-ppp.xsl
2011-06-15 12:07:30 PDT: saving commit script changes for script encap-ppp.xsl
2011-06-15 12:07:30 PDT: summary of script encap-ppp.xsl: changes 0, transients 2 (allowed), syslog 0
2011-06-15 12:07:30 PDT: start loading commit script changes
2011-06-15 12:07:30 PDT: no commit script changes
2011-06-15 12:07:30 PDT: updating transient changes into transient tree
2011-06-15 12:07:30 PDT: finished loading commit script changes
2011-06-15 12:07:30 PDT: copying juniper.db to juniper.data+
2011-06-15 12:07:30 PDT: finished copying juniper.db to juniper.data+
2011-06-15 12:07:30 PDT: exporting juniper.conf
2011-06-15 12:07:30 PDT: merging transient changes
...
configuration check succeeds

After verifying that the script produces the correct changes, issue the commit command to start the commit operation and execute the script.
```
user@host# commit
```

Verification

Verifying the Configuration

Purpose
Action

Purpose

Verify that the correct changes are integrated into the checkout configuration. If there are one or more SONET/SDH interfaces with the IPv4 protocol family enabled, you should see the encapsulation ppp statement added as a transient change to the interface hierarchy.

Action

To view the configuration with transient changes, issue the show interfaces | display commit-scripts configuration mode command. The show interfaces | display commit-scripts command displays all the statements that are in the configuration, including statements that are generated by transient changes. If there are one or more SONET/SDH interfaces with the IPv4 protocol family enabled, the output is similar to the following:

content_copy zoom_out_map
[edit]
user@host# show interfaces | display commit-scripts
... 
so-1/2/3 {
    mtu 576;
    encapsulation ppp; /* Added by transient change. */
    unit 0 {
        family inet {
            address 10.0.0.3/32;
        }
    }
}
so-1/2/4 {
    encapsulation ppp; /* Added by transient change. */
    unit 0 {
        family inet {
            address 10.0.0.4/32;
        }
    }
}
so-2/3/4 {
    encapsulation cisco-hdlc; # Not affected by the script, because IPv4 protocol
                              # family is not configured on this interface.
    unit 0 {
        family mpls;
    }
}

Troubleshooting

Troubleshooting Commit Errors

Problem
Solution

Problem

The CLI generates an invalid transient change error, and the commit fails.

content_copy zoom_out_map
user@host# commit check
error: invalid transient change generated by commit script: encap-ppp.xsl
warning: 1 transient change was generated without [system scripts commit allow-transients]
error: 1 error reported by commit scripts
error: commit script failure

Solution

You must configure the allow-transients statement at the [edit system scripts commit] hierarchy level to enable commit scripts to load transient changes into the checkout configuration.

Configure the following statement to allow transient changes:

content_copy zoom_out_map
[edit]
user@host# set system scripts commit allow-transients

arrow_backward PREVIOUS Remove a Persistent or Transient Configuration Change Using Commit Scripts

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Automation Scripting User Guide

ON THIS PAGE

Example: Generate Persistent and Transient Configuration Changes Using Commit Scripts

Example: Generating a Persistent Change

Requirements

Overview and Commit Script

Configuration

Procedure

Step-by-Step Procedure

Verification

Verifying the Configuration

Purpose

Action

Example: Generating a Transient Change

Requirements

Overview and Commit Script

Configuration

Procedure

Step-by-Step Procedure

Verification

Verifying the Configuration

Purpose

Action

Troubleshooting

Troubleshooting Commit Errors

Problem

Solution

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Automation Scripting User Guide

ON THIS PAGE

Example: Generate Persistent and Transient Configuration Changes Using Commit Scripts

Example: Generating a Persistent Change

Requirements

Overview and Commit Script

Configuration

Procedure

Step-by-Step Procedure

Verification

Verifying the Configuration

Purpose

Action

Example: Generating a Transient Change

Requirements

Overview and Commit Script

Configuration

Procedure

Step-by-Step Procedure

Verification

Verifying the Configuration

Purpose

Action

Troubleshooting

Troubleshooting Commit Errors

Problem

Solution

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