Hardware

Switching Capacity

• QFX5120-48T: 1.08/2.16 Tbps (uni/bidirectional)/1 Bpps
• Switching mode (all models): Cut-through and store-and-forward

Weight

• QFX5120-48T: 24.25 lb (11 kg)

Dimensions (H x W x D)

• QFX5120-48T: 1.72 x 17.36 x 20.48 in. (4.37 x 44.09 x 52.02 cm)

Power Consumption

• QFX5120-48T
  • Max power draw*: 251 W
  • Typical power draw**: 202 W

* Max power consumption measured at 40°C ambient temperature with SR optics at 100% load with IMIX traffic.
** Typical power consumption is measured at 25°C ambient temperature with DACs at 50% load with IMIX traffic, excluding transceivers.
Power consumption is subject to operating conditions and unit-to-unit variations.

Airflow

• Front-to-back (airflow out) for hot aisle deployment
• Back-to-front (airflow in) for cold aisle deployment

Interface Options

• QFX5120-48T
  • 1 management port: 1 x RJ-45 port
  • 1GbE RJ45 (copper): 48 (each port is dual speed supporting 1GbE/10GbE)
  • 40GbE QSFP+: 6 (ports 50 and 51 can be configured as a 4 x 10GbE interface or as 40 Gbps interfaces)
  • 100GbE QSFP28: 6 (ports 50 and 51 can be configured as a 4 x 25GbE interface or as 100 Gbps interfaces)

Common to All Models

• 1 USB 2.0 port
• 1 RS-232 console port
• Supported transceiver and direct attach cable
  • QSFP+ DAC cables: 1/3 m twinax copper
  • QSFP+ optics: SR4, LX4, ESR4, ER4, LR4
  • QSFP28 optics: SR4, ER4, PSM4, CWDM4, LR4
• Versatile four post mounting options for 19-in server rack or datacom rack

Airflow

• Redundant (N+1) and hot-pluggable fan modules for front-to-back and back-to-front airflow
• Redundant variable-speed fans to reduce power draw

Power Supply and Fan Modules

• Dual redundant (1+1) and hot-pluggable 650 W AC/DC power supplies
• 100-240 V single phase AC power
• -48 to -60 V DC power supply
• Redundant 4+1 (QFX5120-48Y/YM and QFX5120-48T) or 5+1 (QFX5120-32C) and hot-pluggable fan modules for front-to-back or back-to-front airflow

Performance Scale (Unidimensional)

• MAC addresses per system: 288,000
• VLAN IDs: 4094
• Number of link aggregation groups (LAGs):
  • 80 (QFX5120-48Y/YM, QFX5120-32C)
  • 64 (QFX5120-48T)
• Number of ports per LAG: 64
• IPv4 unicast routes: 2,000,000 prefixes (RIB); 351,000 prefixes (FIB); 211,000 host routes; 64 ECMP paths
• IPv4 multicast routes: 106,000
• IPv6 unicast routes: 500,000 prefixes (RIB); 172,000 prefixes (FIB); 106,000 host routes
• IPv6 multicast routes: 52,000
• Address Resolution Protocol (ARP) entries: 64,000
• Jumbo frame: 9216 bytes
• Spanning Tree Protocol (STP)
• Multiple Spanning Tree Protocol (MSTP) instances: 64
• VLAN Spanning Tree Protocol (VSTP) instances: 509
• Traffic mirroring
  • Mirroring destination ports per switch: 4
  • Maximum number of mirroring sessions: 4
  • Mirroring destination VLANs per switch: 4
• 100,000 L2 IGMP snooping*

*Scale number may vary depending on the test scenarios and other factors.

Software Features Supported

Layer 2 Features

• STP—IEEE 802.1D (802.1D-2004)
• Rapid Spanning Tree Protocol (RSTP) (IEEE 802.1w); MSTP (IEEE 802.1s)
• Bridge protocol data unit (BPDU) protect
• Loop protect
• Root protect
• RSTP and VSTP running concurrently
• VLAN—IEEE 802.1Q VLAN trunking
• Routed VLAN interface (RVI)
• Port-based VLAN
• Private VLAN (PVLAN)
• VLAN translation
• Static MAC address assignment for interface
• Per VLAN MAC learning (limit)
• MAC learning disable
• Link Aggregation and Link Aggregation Control Protocol (LACP) (IEEE 802.3ad)
• MACsec with AES256 (QFX5120-48YM only)
• Virtual chassis—up to 2 members on QFX5120-48Y, QFX5120-32C and QFX5120-48T, and up to 4 members on QFX5120-48YM

Link Aggregation

• MC-LAG
• LAG load sharing algorithm—bridged or routed (unicast or multicast) traffic
• IP: Session Initiation Protocol (SIP), Dynamic Internet Protocol (DIP), TCP/UDP source port, TCP/UDP destination port
• Layer 2 and non-IP: MAC SA, MAC DA, Ethertype, VLAN ID, source port

Layer 3 Features (IPv4)

• Static routing
• Routing protocols (RIP, OSPF, IS-IS, BGP)
• Virtual Router Redundancy Protocol (VRRP)
• Virtual router
• Dynamic Host Configuration Protocol (DHCP) relay
• Proxy Address Resolution Protocol (ARP)

EVPN-VXLAN Features

• MAC virtual routing and forwarding (MAC-VRF) multiple EVPN instances (EVI) with service-types vlan-based, vlan-aware, vlan-bundle
• Symmetric inter-IRB routing with anycast gateway and EVPN type-5 instances
• Proxy IGMPv2—EVPN route types 6/7/8
• ARP/ND proxy/suppression
• ESI-LAG A/A multihoming using Enterprise and SP-style interfaces
• Enhanced Ethernet loop detection
• Filter-based forwarding on IRB.VGA
• EVPN advanced route policing
• VLAN-id overlapping using SP-style interfaces
• VLAN rewrite support in EVPN-VXLAN enterprise-style 
• (EP-style) interfaces – vlan-id overlap in EP-style interfaces
• OISM - draft-ietf-bess-evpn-irb-mcast
• VLAN rewrite support in EVPN-VXLAN enterprise-style

Multicast Features

• Internet Group Management Protocol (IGMP): v1, v2, v3
• IGMP snooping: v1, v2, and v3 (Layer 2 only)
• IGMP filter
• Protocol Independent Multicast-Sparse Mode (PIM-SM), PIM-Source-Specific Multicast (PIM-SSM), PIM-Dense Mode (PIM-DM) in pure IP fabric use case
• Multicast Source Discovery Protocol (MSDP)

Security and Filters

• Secure interface login and password
• RADIUS
• TACACS+
• Ingress and egress filters: Allow and deny, port filters, VLAN filters, and routed filters, including management port filters
• Filter actions: Logging, system logging, reject, mirror to an interface, counters, assign forwarding class, permit, drop, police, mark
• SSH v1, v2
• Static ARP support in pure IP fabric
• Storm control, port error disable, and autorecovery
• Source MAC address filtering on the port
• DHCP snooping in pure IP fabric use case

Quality of Service (QoS)

• L2 and L3 QoS: Classification, rewrite, queuing
• Rate limiting:
  • Ingress policing: Single-rate two-color policer, two-rate three-color policer
  • Egress policing: Policer, policer mark down action
  • Egress shaping: Per queue on each port
• 10 hardware queues per port (8 unicast and 2 multicast)
• Strict-priority queue (SPQ), shaped-deficit weighted round-robin (SDWRR), weighted random early detection (WRED), weighted tail drop
• 802.1p remarking
• Layer 2 classification criteria: Interface, MAC address, Ethertype, 802.1p, VLAN
• Congestion avoidance capabilities: WRED
• Trust IEEE 802.1p (ingress)
• Remarking of bridged packets
• Default inner to outer DiffServ code point (DSCP) copy for EVPN-VXLAN

IP Storage

• Priority-based flow control (PFC)—IEEE 802.1Qbb, DCBX
• PFC using DSCP and explicit congestion notification (ECN) for ROCEv2

High Availability

• Bidirectional Forwarding Detection (BFD)
• Uplink failure detection

MPLS

• Static label-switched paths (LSPs)
• RSVP-based signaling of LSPs
• LDP-based signaling of LSPs
• LDP tunneling (LDP over RSVP)
• MPLS class of service (CoS)
• MPLS LSR support
• IPv6 tunneling (6PE) (via IPv4 MPLS backbone)
• IPv4 L3 VPN (RFC 2547, RFC 4364)

Management and Analytics Platforms

• Apstra Intent-based System for Data Center
   
• Juniper Mist Wired Assurance for Campus
• Junos Space® Network Director for Campus
• Paragon Insights

Device Management and Operations

• Role-based CLI management and access
• CLI via console, telnet, or SSH
• Extended ping and traceroute
• Junos OS configuration rescue and rollback
• Image rollback
• SNMP v1/v2/v3
• Junos XML management protocol
• sFlow v5
• Beacon LED for port and system
• Inband Flow Analyzer (IFA)
• ZTP
• OpenStack Neutron Plug-in
• Python
• Junos OS event, commit, and OP scripts
• JTI

Traffic Mirroring

• Port-based
• LAG port
• VLAN-based
• Filter-based
• Mirror to local
• Mirror to remote destinations (L2 over VLAN)