MikroTik CRS328-4C-20S-4S+RM 20x SFP 4x SFP+ 4x Combo Dual Boot Rackmount Switch

The MikroTik CRS328-4C-20S-4S+RM (Cloud Router Switch) is a versatile and port-rich 1U rackmount switch that combines SFP, SFP+, and combo port connectivity in a single unit. Its combination of 20 standard SFP ports, 4 SFP+ 10G uplink ports, and 4 flexible combo ports makes it particularly well suited to mixed-media environments where both copper and fibre connections need to be accommodated alongside high-speed uplinks.

Port Configuration & Flexibility

The switch provides 28 independent ports in total. The twenty SFP cages accept standard 1GbE SFP modules — optical or copper — for fibre or RJ45 connections as required. The four SFP+ cages support 10GbE for high-speed uplink or inter-switch connections via fibre, DAC, or compatible SFP+ modules. The four combo ports are a standout feature: each can be used either as a standard Gigabit Ethernet RJ45 port or as an SFP port, providing maximum flexibility for deployment scenarios where the connection type may vary or change over time.

Switching Performance

The 98DX3236 chip delivers non-blocking Layer 2 wire-speed switching across all ports simultaneously. Measured switching performance shows non-blocking Layer 2 throughput of up to 63,167 Mbps at 1518-byte packets, with a full non-blocking Layer 1 capacity of 128,000 Mbps bidirectional. RouterOS-based bridging fast-path delivers up to 1,266.6 Mbps throughput at 1518-byte packets, with routing fast-path at the same level — confirming capable Layer 3 forwarding performance in addition to wire-speed Layer 2 switching.

Dual Operating System — RouterOS & SwitchOS

The CRS328-4C-20S-4S+RM supports dual boot between RouterOS and SwitchOS. RouterOS provides the full MikroTik feature set including Layer 3 routing, VLAN management, firewall, QoS, MPLS, VPN, and advanced switching features, manageable via WinBox, WebFig, or CLI. SwitchOS offers a simplified, switch-oriented management interface for operators who prefer traditional managed switch workflows. Both operating systems are pre-installed and licensed at no additional cost. A dedicated mode button on the unit provides convenient OS switching.

Power & Cooling

The unit features two PSU slots with failover functionality, accepting 100–240 V AC at 50–60 Hz, providing power redundancy for high-availability deployments. Maximum power consumption is 43 W. Two fans handle active cooling. On-board CPU temperature and voltage monitors support health management.

Build & Form Factor

The CRS328-4C-20S-4S+RM occupies 1U of rack space at 443 × 194 × 44 mm. It is designed to operate between -20°C and 60°C, with an MTBF of approximately 200,000 hours at 25°C. An RJ45 serial console port provides out-of-band management access. The package includes a K-54 kit, rackmount ears, and two IEC power cords.

Use Cases

The CRS328-4C-20S-4S+RM is well suited for ISP aggregation and distribution layers, enterprise or campus network distribution switching, data centre access-layer switching with 10G uplinks, environments requiring mixed copper and fibre SFP connectivity, and any deployment where a high-port-density managed switch with dual-boot OS flexibility and redundant power is required.

Key Specifications at a Glance

• Product Code: CRS328-4C-20S-4S+RM
• SFP Ports: 20x 1GbE
• SFP+ Ports: 4x 10GbE
• Combo Ports: 4x (Gigabit Ethernet RJ45 or SFP)
• Total Independent Ports: 28
• Switch/CPU Chip: 98DX3236, dual-core 800 MHz, ARM 32-bit
• RAM: 512 MB
• Storage: 16 MB FLASH
• Operating System: RouterOS / SwitchOS (dual boot, pre-installed and licensed)
• Non-Blocking Layer 2 Throughput: Up to 63,167 Mbps (1518-byte)
• Non-Blocking Layer 1 Capacity: 128,000 Mbps (bidirectional)
• Serial Console: RJ45
• Mode Button: Yes
• AC Power Input: 100–240 V, 50–60 Hz
• PSU Slots: 2 (redundant with failover)
• Max Power Consumption: 43 W
• Cooling: 2 fans
• Form Factor: 1U rackmount
• Dimensions: 443 × 194 × 44 mm
• Operating Temperature: -20°C to 60°C
• MTBF: ~200,000 hours at 25°C
• Certifications: CE, EAC, RoHS
• Included: K-54 kit, rackmount ears, 2x IEC cords