Juniper Networks

JNCIA-Junos

Juniper Networks Certified Internet Associate – Junos

Associate JN0-104 Content Available

Build a solid foundation in Junos OS and core networking with Juniper's entry-level certification.

Practice JNCIA-Junos Questions Study Notes Exam Topics
Exam Code
JN0-104
Duration
90 minutes
Questions
65
Passing Score
Determined by Juniper Networks
Validity
3 years
Exam Cost
$200 USD
Overview

About JNCIA-Junos

The JNCIA-Junos (JN0-104) is the entry-level certification in the Juniper Networks certification programme. It validates knowledge of networking fundamentals and core Junos OS concepts, including the Junos architecture, CLI, routing fundamentals, routing policy, and firewall filters. Junos OS powers the full Juniper portfolio — from the EX Series switches and MX Series routers to the SRX Series firewalls and QFX data centre switches. Passing the JNCIA demonstrates a working knowledge of the platform that underpins all higher-level Juniper certifications (JNCIS, JNCIP, JNCIE). The JNCIA-Junos is ideal for network engineers new to Juniper, IT professionals transitioning from other vendors, and students pursuing a career in networking who want a vendor certification alongside their foundational studies.

Prerequisites
Basic understanding of networking concepts (OSI model, IP addressing) No formal prerequisites — open to all candidates
Exam Domains

What you need to know

5 domains, 64 objectives. Click a domain to expand its topics.

🌿
Junos OS Fundamentals
Junos architecture, software releases, initial setup, rescue configuration, and the commit model.
25%
  • Describe the Junos OS architecture (separate Routing Engine and Packet Forwarding Engine)
  • Explain the role of the Routing Engine (RE) — control plane, routing protocols, management
  • Explain the role of the Packet Forwarding Engine (PFE) — data plane, hardware forwarding
  • Describe the Junos software release numbering convention (major.minor[S/R/B]-build)
  • Perform initial Junos device setup (hostname, root password, management interface, SSH)
  • Configure out-of-band management using the fxp0 (management) interface
  • Describe factory-default configuration and how to return to it
  • Configure and restore from a rescue configuration
  • Understand the Junos candidate configuration model (configuration is not live until committed)
  • Use commit, commit confirmed, commit check, and rollback commands
  • Explain the significance of rollback 0 through rollback 49 (stored configurations)
  • Configure system services (SSH, Telnet, NETCONF, HTTP) and their security implications
  • Describe Junos software upgrade procedure (request system software add)
💻
User Interface Options
CLI operational and configuration modes, interface naming, hierarchy navigation, and J-Web.
20%
  • Navigate between CLI operational mode and configuration mode (configure / exit)
  • Use operational mode commands (show, ping, traceroute, clear, request)
  • Understand the hierarchical configuration structure (stanzas, brackets, levels)
  • Navigate the configuration hierarchy using edit, up, top, and show commands
  • Use set, delete, deactivate, and activate commands to modify configuration
  • {'Interpret Junos interface naming conventions (ge-0/0/0': 'type-FPC/PIC/port)'}
  • Use the pipe (|) operator with display set, match, and count for output filtering
  • Compare the advantages of set format vs stanza format for configuration viewing
  • Use the ? (help) key for context-sensitive command completion
  • Perform configuration comparison with show | compare
  • Load configuration from a file (load merge, load override, load replace, load patch)
  • Access the J-Web graphical management interface and describe its capabilities
  • Use the Junos Space Network Management Platform for multi-device management
🗺️
Routing Fundamentals
Routing tables, preference values, static routes, OSPF/BGP overview, and route resolution.
30%
  • Describe the purpose and structure of the Junos routing table (inet.0 for IPv4 unicast)
  • Explain routing table preference values (administrative distance) for each protocol
  • Understand the route selection algorithm (most-specific prefix, lowest preference, lowest metric)
  • Configure static routes with a next-hop IP address
  • Configure a static default route (0.0.0.0/0) with a next-hop
  • Configure qualified next-hop for static route metric manipulation
  • Use the retain option to keep static routes in the forwarding table when the protocol is disabled
  • Use the no-readvertise option to prevent static routes from being redistributed
  • Describe the difference between active routes, inactive routes, and hidden routes
  • Verify routing table contents (show route, show route protocol static, show route detail)
  • Describe OSPF neighbour relationships and link-state database concepts (overview level)
  • Describe BGP peer sessions, AS numbers, and path selection concepts (overview level)
  • Configure and verify a loopback interface (lo0) as the router ID
  • Describe the forwarding table (show route forwarding-table) and its role in packet forwarding
📋
Routing Policy
Policy terms, match conditions, actions, import/export application, prefix lists, and communities.
15%
  • Describe the default routing policy behaviour (import and export defaults per protocol)
  • Explain the structure of a routing policy (policy-statement, terms, from, then)
  • Configure match conditions in routing policy (route-filter, prefix-list, protocol, community)
  • Configure policy actions (accept, reject, next-term, next-policy)
  • Configure modifying actions (set local-preference, set metric, add community)
  • Apply routing policies as import and export policies on routing protocols
  • Understand the policy evaluation order and how multiple policies chain together
  • Create and reference prefix lists in routing policy
  • Define and match BGP community values in routing policy
  • Use the load-balance per-packet and load-balance per-flow actions in routing policy
  • Verify policy evaluation using show policy and test policy commands
  • Describe the difference between import policy (affects routing table) and export policy (affects advertisements)
🔒
Firewall Filters
Filter term structure, match conditions, actions, stateless filtering, and loopback protection.
10%
  • Describe Junos firewall filters as stateless packet filters (ACLs)
  • Understand the filter term structure (from, then) and implicit discard at end of filter
  • Configure match conditions in firewall filters (source-address, destination-address, protocol, port, prefix-list)
  • Configure filter actions (accept, discard, reject, count, log, syslog, sample)
  • Apply a firewall filter to an interface in the input and output direction
  • Apply a firewall filter to the loopback (lo0) interface to protect the Routing Engine
  • Understand the difference between discard (silently drop) and reject (ICMP unreachable)
  • Compare stateless firewall filters to stateful security policies (SRX firewall)
  • Use the count action to count matched packets for monitoring and troubleshooting
  • Verify firewall filter statistics (show firewall filter <name>)
  • Configure a filter to rate-limit traffic using a policer
  • Design a loopback protection filter allowing management protocols and blocking everything else
Resources

Study & Practice

Practice JNCIA-Junos Questions Official JNCIA-Junos Exam Page Juniper Open Learning Junos Documentation Schedule your exam via Pearson VUE