e Juniper Networks (JNCIA-Junos) INTERVIEW QUESTIONS
🔰 Juniper Basics
1️⃣ What is Juniper Networks?
Juniper Networks is a company that provides networking devices like routers, switches, firewalls, mainly used by ISPs and enterprises.
2️⃣ What is Junos OS?
Junos OS is Juniper’s network operating system, used across all Juniper devices (routers, switches, firewalls).
3️⃣ What is the advantage of Junos OS?
- Single OS for all devices
- Stable and secure
- Separation of control plane & data plane
4️⃣ What is the control plane in Juniper?
Handles routing protocols and management.
5️⃣ What is the data plane?
Forwards traffic based on routing decisions.
🔌 Juniper Interface & Configuration
6️⃣ What is the default interface state in Juniper?
❌ Interfaces are disabled by default
Command to enable:
set interfaces ge-0/0/0 enable
7️⃣ What are the main configuration modes in Junos?
- Operational mode
- Configuration mode
8️⃣ How do you enter configuration mode?
configure
9️⃣ How do you commit changes?
commit
🔟 Difference between commit and save?
- commit → applies config
- save → saves config file
🌐 IP Addressing (Juniper)
1️⃣1️⃣ How do you configure an IPv4 address?
set interfaces ge-0/0/0 unit 0 family inet address 192.168.1.1/24
1️⃣2️⃣ How do you configure an IPv6 address?
set interfaces ge-0/0/0 unit 0 family inet6 address 2001:db8::1/64
1️⃣3️⃣ How do you check interface status?
show interfaces terse
1️⃣4️⃣ How do you check IP routing table?
show route
🔁 Routing Basics
1️⃣5️⃣ What routing protocols does Juniper support?
- Static
- RIP
- OSPF
- IS-IS
- BGP
1️⃣6️⃣ How do you configure a static route?
set routing-options static route 0.0.0.0/0 next-hop 192.168.1.254
1️⃣7️⃣ What is a default route?
A route used when no specific route exists.
🔐 Security Basics (SRX)
1️⃣8️⃣ What is Juniper SRX?
A firewall device used for network security.
1️⃣9️⃣ What are security zones?
They define trust levels (trust, untrust).
2️⃣0️⃣ What is NAT in Juniper?
Translates private IPs to public IPs.