Commit scripts are a type of on-box automation script in Junos OS that are specifically designed to be executed during the commit process. When a user issues the commit command to apply a candidate configuration, the commit script is invoked. These scripts can be used to enforce custom configuration rules, validate the configuration against specific policies, or automatically generate additional configuration statements based on the changes being committed.

A. event: Event scripts are triggered by system events, such as system log messages or SNMP traps, as defined within an event policy, not directly by the commit action itself.

B. SNMP: SNMP scripts are invoked when a network management system requests data for a specific, non-standard Object Identifier (OID), extending the device's MIB.

D. operation: Operation (op) scripts are executed manually by a user from the operational mode CLI to perform custom diagnostic or administrative tasks.

1. Juniper Networks. (2023). Junos OS Automation Scripting User Guide. "Understanding the Types of Junos OS Automation Scripts" section. Retrieved from https://www.juniper.net/documentation/us/en/software/junos/automation-scripting/topics/concept/automation-scripting-scripts-overview.html.

Quote: "Commit scripts are invoked when you issue the commit command."

2. Juniper Networks. (2023). Junos OS Automation Scripting User Guide. "Commit Scripts" section. Retrieved from https://www.juniper.net/documentation/us/en/software/junos/automation-scripting/topics/concept/automation-scripting-commit-scripts-overview.html.

Quote: "Commit scripts enforce custom configuration rules. They are invoked automatically during a commit operation."