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Compare Juniper and Cisco CLI Commands

Comparing Juniper and Cisco CLI Commands: A Comprehensive Guide

In the world of network administration, Cisco and Juniper represent two dominant approaches to network device management through Command Line Interface (CLI). While both accomplish similar networking tasks, their command structures, configuration philosophies, and operational models differ significantly. This report explores these differences to help network engineers understand how these platforms compare and how to transition between them.

Fundamental Architectural Differences

The most significant difference between Junos OS (Juniper) and IOS (Cisco) lies in their architectural approaches to command organization and configuration management.

Command Structure

Juniper’s Junos OS organizes commands hierarchically within curly braces, creating a tree-like structure with clear parent-child relationships. In contrast, Cisco’s IOS uses a flat file structure where commands are entered sequentially[1]. This fundamental architectural difference impacts how administrators interact with each platform.

Junos configuration resembles programming languages with its structured hierarchy:

interfaces {
    ge-0/0/3 {
        unit 0 {
            family inet {
                address 10.0.0.0/31;
            }
        }
    }
}

While Cisco IOS uses a mode-based approach:

interface fa0/0
 ip address 1.1.1.1 255.255.255.0

Configuration Management Model

Another core difference is how configurations are applied:

  • Junos OS: Uses a candidate configuration model where changes are stored in a temporary area until explicitly committed to the active configuration
  • Cisco IOS: Applies changes to the running configuration immediately after being entered[1:1]

This distinction fundamentally changes how administrators approach configuration tasks, especially in production environments where configuration errors could cause service disruptions.

Command Mode and Navigation Comparison

Command Modes

Cisco IOS organizes commands into hierarchical modes:

Prompt Abbreviation Description
Router> U User EXEC mode, first level of access
Router# P Privileged EXEC mode, accessible with “enable” command
Router(config)# G Global configuration mode
Router(config-if)# I Interface configuration mode
Router(config-router)# R Routing protocol configuration mode
Router(config-line)# L Line level configuration mode
Router(config-vlan)# V VLAN configuration mode
Switch(vlan)# VD VLAN database mode

Juniper employs a simpler mode structure:

  • Operational mode (default after login)
  • Configuration mode (entered via configure command)
  • Within configuration mode, administrators navigate a hierarchical structure using edit commands[2]

Keyboard Shortcuts

Both platforms offer keyboard shortcuts for CLI efficiency, though they implement them differently. Junos OS includes Unix-like shortcuts for cursor movement and text manipulation[2:1][3]:

Keyboard sequence Action
Ctrl+b Move cursor back one character
Esc+b or Alt+b Move cursor back one word
Ctrl+f Move cursor forward one character
Ctrl+a Move cursor to beginning of command line
Ctrl+e Move cursor to end of command line

Common Command Equivalents

The table below shows common network administration tasks and their equivalent commands on both platforms:

Function Cisco Command Juniper Command
View running configuration show running-config show configuration
View device uptime show clock show system uptime
View interface status show interface [intfc] show interfaces [intfc] detail
View interface descriptions show interface | incl (proto|Desc) show interfaces description
Check system version show version show version
View routing table show ip route show route
Ping a host ping [dest] ping [dest] rapid (for Cisco-like output)
Traceroute traceroute traceroute
View logs show logging show log
Check hardware show diags show chassis hardware

Protocol-Specific Commands

For network protocols, the command equivalents include:

BGP Commands

Cisco Command Juniper Command
show ip bgp summary show bgp summary
show ip bgp show route protocol bgp
show ip bgp neighbors show bgp neighbour

OSPF Commands

Cisco Command Juniper Command
show ip ospf neighbor show ospf neighbour

Configuration Management Approaches

Basic Configuration Tasks

Changing the Hostname

Cisco:

Router(config)# hostname CORE-RTR-HQ

Juniper:

root@# set host-name CORE-RTR-HQ

Creating VLANs

Cisco:

CORE-RTR-HQ(config)# vlan 20
CORE-RTR-HQ(config)# name sales

Juniper:

root@CORE-RTR-HQ# set vlans sales
root@CORE-RTR-HQ# set vlans sales vlan-id 20

Power of Commit Model

Juniper’s commit model offers several advantages for configuration management:

  1. Commit Confirmed: Automatically rolls back changes unless confirmed within a specified timeframe
commit confirmed 5

This command commits configuration but will roll back in 5 minutes unless confirmed[4] 2. Configuration Comparison:

show | compare

Shows differences between candidate and active configurations 3. Rollback Capabilities:

rollback 3

Loads the configuration from 3 commits ago[4:1] 4. Configuration Pattern Replacement:

replace pattern

Enables search and replace across the configuration[4:2]

These capabilities make Juniper’s configuration management particularly robust for complex network environments.

Advanced CLI Features Comparison

Juniper Advanced Features

Juniper’s CLI offers several advanced capabilities that distinguish it from Cisco:

  1. Commit Scripts: Allows automated validation of configurations before commit
  2. Configuration Groups: Enables template-based configuration to apply common settings across multiple devices
  3. Operation Scripts: Automates routine operational tasks
  4. Annotation: Allows adding comments to configuration items
annotate interfaces ge-0/0/0 "Connection to core switch"

Cisco Advanced Features

Cisco has its own strengths:

  1. Configuration Templates: Through tools like Embedded Event Manager (EEM)
  2. Conditional Configuration: Using if-then statements in certain IOS versions
  3. Wider Device Support: Commands often work across a broader range of hardware

Transitioning Between Platforms

For network engineers transitioning from Cisco to Juniper, several resources can help ease the learning curve:

  1. Juniper’s “Day One” guides, particularly “Junos for IOS Engineers”[5]
  2. Free “Migrating from the Cisco CCNA to the JNCIA-Junos” course on Junos Genius website[5:1]
  3. Command cheat sheets comparing the two platforms[6][7]
  4. Lab workbooks designed for Cisco engineers learning Juniper[5:2]

A practical approach is to download a free vSRX (virtual Juniper firewall) for hands-on practice[5:3].

Conclusion

While Cisco and Juniper achieve similar networking objectives, their CLIs reflect fundamentally different design philosophies:

  • Cisco’s IOS offers immediate configuration application with a mode-based interface familiar to many network engineers, making it approachable for beginners.
  • Juniper’s Junos provides a more structured, programming-like approach with superior configuration management features like the commit model, candidate configurations, and rollback capabilities.

Many engineers who have worked with both platforms often prefer Juniper’s CLI for its consistency, robust configuration management, and logical structure[4:3]. However, Cisco’s widespread deployment means its CLI remains the reference standard for many network engineers.

The best approach is to understand the underlying network technologies rather than focusing solely on vendor-specific commands. As one network professional advised, “My recommendation is to learn the technology, not the vendor… At that point it’s just how that vendor did the CLI”[4:4].

References

  1. Reddit: “Juniper CLI command cheat sheet”[8]
  2. WebSentra: “Cisco Commands Cheat Sheet”[9]
  3. Orhan Ergun: “Palo Alto CLI Commands: A Comparison with Cisco and Juniper”[10]
  4. IPCisco: “Cisco Commands Cheat Sheet | Cisco vs Juniper vs Nokia Huawei”[11]
  5. Scribd: “Junos Commands Vs IOS Commands”[1:2]
  6. Juniper Community: “Equivalent Junos commands to Cisco BGP VRF redistribute commands”[12]
  7. Cisco: “Cisco IOS Configuration Fundamentals Command Reference”[13]
  8. Reddit: “Cisco iOS Juniper JunOS”[5:4]
  9. Juniper Networks: “CLI User Guide for Junos OS”[2:2]
  10. IPWithEase: “CISCO JUNIPER EQUIVALENT COMMANDS – CLI CHEATSHEET”[6:1]
  11. Cisco: “Command References – Cisco IOS XE 17”[14]
  12. MyNetworkNexus: “CISCO vs Juniper – Comparing 10 Common Network Commands”[15]
  13. Cisco: “Command References – Cisco IOS 15.0S”[16]
  14. CmdRef.net: “Juniper Junos CLI Commands(SRX/QFX/EX)”[17]
  15. Reddit: “Cisco to Juniper”[4:5]
  16. Scribd: “Juniper Cheat Sheet”[18]
  17. Scribd: “Cisco-Juniper Commands Comparison PDF”[7:1]
  18. Juniper Networks: “CLI Command Reference Guide”[3:1]

  1. https://www.scribd.com/document/319472408/Junos-Commands-vs-IOS-Commands ↩︎ ↩︎ ↩︎

  2. https://www.juniper.net/documentation/us/en/software/junos/cli/cli.pdf ↩︎ ↩︎ ↩︎

  3. https://www.juniper.net/documentation/us/en/software/atp-appliance/atp-appliance-cli-reference/atp-appliance-cli-reference.pdf ↩︎ ↩︎

  4. https://www.reddit.com/r/networking/comments/rbrbc0/cisco_to_juniper/ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎

  5. https://www.reddit.com/r/Juniper/comments/hbaljn/cisco_ios_juniper_junos/ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎

  6. https://ipwithease.com/wp-content/uploads/2020/05/CISCO-JUNIPER-CLI-CHEATSHEET.pdf ↩︎ ↩︎

  7. https://www.scribd.com/document/342065019/Cisco-Juniper-Commands-Comparison-pdf ↩︎ ↩︎

  8. https://www.reddit.com/r/Juniper/comments/q1doiy/juniper_cli_command_cheat_sheet/ ↩︎

  9. https://www.websentra.com/cisco-commands-cheat-sheet/ ↩︎

  10. https://orhanergun.net/palo-alto-cli-commands-a-comparison-with-cisco-and-juniper ↩︎

  11. https://ipcisco.com/cli-commands-cheat-sheets/ ↩︎

  12. https://community.juniper.net/discussion/equivalent-junos-commands-to-cisco-bgp-vrf-redistribute-commands ↩︎

  13. https://www.cisco.com/c/en/us/td/docs/ios/fundamentals/command/reference/cf_book.html ↩︎

  14. https://www.cisco.com/c/en/us/support/ios-nx-os-software/ios-xe-17/products-command-reference-list.html ↩︎

  15. https://mynetworknexus.com/cisco-vs-juniper-comparing-10-common-network-commands/ ↩︎

  16. https://www.cisco.com/c/en/us/support/ios-nx-os-software/ios-15-0s/products-command-reference-list.html ↩︎

  17. https://cmdref.net/hardware/junos/index.html ↩︎

  18. https://www.scribd.com/document/336458262/Juniper-Cheat-Sheet ↩︎

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