Arrow Electronics, Inc.

Junos Troubleshooting (JT)


LENGTH: 16 Hours (2 days)

PRICE: £1,700.00


This two-day course provides foundational troubleshooting skills. In this course, students will learn to use common Junos troubleshooting commands and tools.

This course will help students to acquire the skills needed to perform basic troubleshooting on Juniper devices.

Students will learn to troubleshoot the control plane, the forwarding plane, and the secure the connection between the two planes from DDoS attacks.

Students will also learn to troubleshoot common network services such as DHCP, DNS, and authentication services.

Students will get hands-on practice using vMX Series, vSRX Series, and vQFX Series devices in the lab.

The course is based on Junos OS Release 22.3R1.

Note: For those who have previously taken the Juniper Troubleshooting in the NOC (JTNOC) course, we recommend moving to the next course in the learning path, Advanced Junos Troubleshooting.


• Describe Junos products and related information and recovery options.

• Explain various tools that can be used to troubleshoot Junos devices.

• Explain Junos CLI commands used in troubleshooting.

• Identify and isolate hardware issues.

• Troubleshoot problems with the control plane.

• Describe control plane protection features.

• Troubleshoot problems with interfaces and other data plane components.

• Describe the staging and acceptance methodology.

• Troubleshoot networking services.

• Troubleshoot high availability features.

• Describe how to monitor your network with SNMP, RMON, Junos Telemetry Interface, Junos Traffic Vision (formerly known as JFlow), and port mirroring.


This course is for people who troubleshoot Juniper devices running the Junos OS, which includes network operators, engineers, administrators, support personnel, and reseller support personnel.


The prerequisite knowledge includes the following courses, or equivalent knowledge:

• Juniper Technical Support Fundamentals

• Introduction to the Junos Operating System


Day 1


Course Introduction

Junos Product Families

• Describe the architectural philosophy of devices that run the Junos OS and understand how this relates to troubleshooting

• Describe traffic processing for transit and exception traffic

• Describe the function and components of the RE and PFE within a device running the Junos OS

• Describe FRUs

• Describe current Junos product families and understand where to go for detailed information about your hardware


Lab 1: Identifying Hardware Compon


Troubleshooting Toolkit

• Describe various tools that can be used to troubleshoot devices that run the Junos operating system

• Explain JTAC recommendations for current best-practices that facilitate troubleshooting


Lab 2: Using Monitoring Tools and Establishing a Baseline


Hardware and Environmental Conditions

• Describe the key commands and features used to monitor storage and memory issues

• Describe the key commands and features that you can use to monitor software installations

• Determine how to find potential hardware problems using system logs

• Describe the key commands that you can use to monitor hardware and environmental issues


Lab 3: Monitoring Hardware and Environmental Conditions


Control Plane

• Monitor and troubleshoot system processes that reside in the control plane

• Utilize a logical approach to troubleshooting routing issues that reside in the control plane

• Monitor and troubleshoot basic bridging and ARP functionalities


Lab 4: Control Plane Monitoring and Troubleshooting


Control Plane Protection

• Describe DDoS attacks

• Explain and configure the DDoS protection feature

• Outline using firewall filters to protect the control plane


Lab 5: Protecting the Control Plane


Day 2


Data Plane: Interfaces

• Describe physical and logical interface properties

• Deactivate and disable interfaces

• Perform loopback testing

• Use operational mode commands to monitor and troubleshoot Ethernet interfaces


Lab 6: Monitoring and Troubleshooting Ethernet Interfaces


Data Plane: Other Components

• Recognize data plane problems and components

• Monitor and troubleshoot data plane forwarding

• Monitor load balancing

• Troubleshoot firewall filter and policer issues


Lab 7: Isolating and Troubleshooting PFE Issues


Staging and Acceptance Testing

• Perform a Junos device initial inspection and power-on

• Perform general system checks recommended for a newly deployed Junos device

• Determine the status of new interface connections by performing loopback testing and monitoring


Troubleshooting Network Services

• Discuss DNS, DHCP, NTP, SSH, SNMP, and telemetry

• Explain authentication issues

• Discuss MACsec issues

• Discuss LLDP issues


Lab 8: Troubleshooting Network Services


Troubleshooting High Availability Features

• Discuss LACP, BFD, NSR, and NSB issues

• Explain graceful routing engine switchover

• Explain graceful restart

• Discuss Aggregated Ethernet issues

• Discuss MC-LAG issues

• Discuss VRRP issues


Network Monitoring

• Explain how to configure and monitor SNMP

• Discuss how to configure and monitor RMON

• Describe how to use the Junos telemetry interface

• Describe how to use flow monitoring


Lab 9: Monitoring the Network


Appendix A: Junos RPM

• Explain the purpose of the Junos RPM

• Describe the components of the Junos RPM

• Implement Junos RPM Probes

• Monitor the deployed Probes

Follow on courses

Advanced Junos Troubleshooting (AJT)

Further Information

Related Juniper Product

Junos OS • vSRX Series • vMX Series • vQFX Series

Session Dates
Time Zone

12 Aug 2024

Virtual Training Class - TP



Instructor Led Online

£ 1,700.00

30 Sep 2024

Virtual Training Class - TP



Instructor Led Online

£ 1,700.00