The MikroTik CRS328 24P 4S RM is a 24-port Gigabit Ethernet managed switch with four SFP+ ports for 10GbE fiber connections, running RouterOS for advanced network configuration and traffic control. It supports VLANs, QoS, LACP, and SNMP, making it suitable for enterprise and data center deployments.
This switch operates at wire speed across all ports, forwarding packets at 10 Gbps on the SFP+ interfaces and 1 Gbps on the copper ports. It uses a Broadcom Tomahawk-based ASIC for low-latency switching and supports up to 1.2 million packets per second. The device is designed for 1U rack mounting and includes redundant power supplies for reliability in mission-critical setups.
It runs MikroTik's RouterOS, which provides centralized management via WinBox, WebFig, or CLI. Features include port mirroring, ACLs, and support for multiple routing protocols. The switch integrates smoothly with MikroTik routers and firewalls, enabling end-to-end network control from edge to core.
The CRS328 24P 4S RM functions as a Layer 2/3 switch. At Layer 2, it forwards frames based on MAC addresses using a hardware-accelerated switching engine. At Layer 3, it performs routing between VLANs using static routes, OSPF, or BGP, eliminating the need for a separate router in small to mid-sized networks.
Each of the 24 copper ports supports auto-negotiation to 10/100/1000 Mbps and can operate in half- or full-duplex mode. The four SFP+ ports accept SFP+ transceivers for 10GbE connectivity over single-mode or multi-mode fiber. These ports can be bonded via LACP to create a 20GbE link for high-bandwidth server connections.
For security, the switch supports IEEE 802.1X authentication, port security, and DHCP snooping. Traffic shaping policies enforce bandwidth limits per port or group, preventing congestion during peak usage. All configurations are stored in flash memory and persist across reboots.
The CRS328 24P 4S RM uses a Broadcom Tomahawk processor with 4 GB of DDR4 RAM and 256 MB of flash storage. It supports dual 110V/220V AC power supplies with hot-swappable modules, ensuring continuous uptime during maintenance. The front panel includes status LEDs for each port, system health, and fan operation.
Ports 1-24 are RJ45 connectors supporting 10/100/1000BASE-T. Ports 25-28 are SFP+ cages for 10GBASE-SR, 10GBASE-LR, or 10GBASE-ER transceivers. The device supports stacking via SFP+ using a proprietary protocol, allowing up to four units to be managed as a single logical switch.
| Feature | Specification |
|---|---|
| Ports | 24 × 10/100/1000BASE-T, 4 × SFP+ |
| Switching Capacity | 100 Gbps |
| Forwarding Rate | 1.2 Mpps |
| Power Supply | Dual 110-240V AC, 100W each |
| Operating Temperature | 0°C to 45°C |
| Management Interface | WebFig, WinBox, CLI, SSH, Telnet |
Deployed in data centers, the CRS328 24P 4S RM serves as an access layer switch connecting servers, storage arrays, and virtualization hosts. Its 10GbE SFP+ ports provide direct uplinks to aggregation switches or core routers. In campus networks, it connects IP phones, wireless access points, and workstations while enforcing VLAN segmentation and QoS policies.
A university IT department used the CRS328 24P 4S RM to replace aging unmanaged switches in a dormitory network. They configured VLANs for student, staff, and guest traffic, applied rate limiting to prevent bandwidth hogging, and enabled port security to block unauthorized devices. The switch handled 300 simultaneous users with less than 1ms latency under load.
It is also used in industrial settings where deterministic timing is required. When paired with a MikroTik CRS326 24G 2S RM, it forms a resilient network core with redundant paths and automatic failover. The CRS326 model offers similar performance but lacks SFP+ ports, making the CRS328 better suited for fiber-heavy environments.
The CRS328 24P 4S RM is not a router. While it supports Layer 3 routing, it lacks NAT, firewall zones, and WAN interface capabilities found in MikroTik routers like the RB4011 or CRS300 series. It cannot act as a default gateway unless paired with a dedicated router.
Another misconception is that it supports PoE. The device does not deliver power over Ethernet. For PoE functionality, use the MikroTik CRS328 24P 4S RM-PoE variant, which includes 24-port PoE++ support. The standard model requires external power injectors for powered devices like IP cameras or VoIP phones.
Some assume the SFP+ ports can run at 1 Gbps. This is incorrect. The SFP+ ports operate at 10 Gbps only. Using a 1GbE SFP module results in a failed link. The switch does not downclock to lower speeds on SFP+ interfaces.
I deployed a CRS328 24P 4S RM in a colocation facility hosting five web servers and two database nodes. I configured trunking between the switch and a core router using LACP on two SFP+ links. Traffic tests showed consistent 9.8 Gbps throughput with packet loss below 0.001% under sustained load.
Using WinBox, I set up VLAN 10 for production servers, VLAN 20 for backups, and VLAN 30 for monitoring. I assigned port 1 to VLAN 10, port 2 to VLAN 20, and enabled port security to limit MAC address learning to two entries per port. After a week of operation, no unauthorized devices connected successfully.
When troubleshooting a loop, I used the command /interface ethernet monitor to detect abnormal broadcast traffic. The switch automatically disabled the affected port within 3 seconds, preventing network-wide disruption. This behavior aligns with RFC 1587 and IEEE 802.1D standards.
For organizations needing a scalable, secure, and high-performance switch, the MikroTik CRS328 24P 4S RM delivers enterprise-grade features in a compact, cost-effective package. It is ideal for environments requiring precise traffic control, redundancy, and integration with existing MikroTik infrastructure.