JN0-106 Operational Monitoring and Maintenance Practice Question
Which TWO methods can be used to restore a previous configuration on a Juniper device? (Select two.)
⚠ Common exam trap
Many exam-takers confuse 'rollback 0' with restoring a previous configuration, not realizing that rollback 0 refers to the current active configuration, while rollback 1 or higher is needed to access a prior committed configuration.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
load override /config/rescue.conf
Option A, `load override /config/rescue.conf`, is correct because the rescue configuration is a saved, known-good configuration file that can be loaded with the `load override` command to replace the entire current candidate configuration, after which a `commit` restores the device to that prior state. Option C, `rollback 1`, is correct because Junos retains the last 49 committed configurations, and `rollback 1` loads the immediately previous committed configuration into the candidate, which can then be committed to restore the earlier configuration. Option B, `commit confirmed`, is not a restore method; it activates a configuration temporarily and auto-rolls back unless confirmed, so it is used for safe changes, not for restoring a previous config. Option D, `load replace previous`, is invalid syntax—`load replace` requires a specific file or terminal input, and there is no `previous` keyword for it. Option E, `rollback 0`, loads the currently active (most recent) committed configuration, so it does not restore an earlier configuration.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
load override /config/rescue.conf
Why this is correct
The rescue configuration is a dedicated backup file stored at /config/rescue.conf. The 'load override' command replaces the entire candidate configuration with the contents of this file, which can then be committed to restore the device to a known-good state. This is a valid and reliable method for recovering a previous configuration, especially in disaster recovery scenarios.
- ✗
commit confirmed
Why it's wrong here
The 'commit confirmed' command is a temporary commit that automatically rolls back to the previous configuration if a confirming commit is not issued within the default timeout (usually 10 minutes). It is intended to test whether a new configuration is safe, not to load an earlier configuration. Since it does not reference any stored configuration snapshot, it cannot be used as a restore method.
- ✓
rollback 1
Why this is correct
The 'rollback' command is a built-in Junos feature that loads one of the previously committed configurations from the rollback database. 'rollback 1' specifically selects the configuration that was committed immediately before the current candidate, copying it into the candidate configuration space. After a 'commit', this restores the device to the exact state of that earlier configuration, making it a correct method of restoration.
- ✗
load replace previous
Why it's wrong here
'load replace previous' is not a syntactically valid Junos command. The 'load' statement accepts options such as 'override', 'merge', 'replace', 'patch', and 'set', but these require a filename or 'terminal' as an argument, not the word 'previous'. As a result, the CLI will reject the command with an error, so it cannot restore any configuration.
- ✗
rollback 0
Why it's wrong here
'rollback 0' reloads the candidate configuration from the currently committed configuration, effectively discarding any uncommitted edits. It does not access an earlier configuration state; instead, it re-uses the very same configuration that is already active. Therefore it cannot return the device to a previous configuration and is not a valid restore method.
Visual reference
Go deeper
Related to this question
About these practice questions
This JN0-106 question is part of Courseiva's 326-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This JN0-106 practice question is part of Courseiva's free Juniper Networks certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the JN0-106 exam.