SVI

SVI stands for Switched Virtual Interface. It is a virtual interface configuring Layer 3 routing for VLAN on a switch. SVI allows traffic to be routed between VLANs by providing a default gateway for the VLAN. SVI also includes Layer 3 IP connectivity to the switch and supports bridging and routing protocols. It is different from the physical interface of a router. By using SVI, multiple VLANs can share the same physical interface on the switch, and each virtual LAN has its own logical interface and broadcast domain.

Why Do We Need SVI

SVI is a very important technology in modern network communication, especially in enterprise networks and data centers. The following are the reasons why SVI is needed:

1. Realize communication between VLANs

VLAN is to create multiple logically isolated network segments in the same physical network. Each VLAN has its broadcast domain. In the absence of SVI, they need to communicate with each other through a router. SVI can enable the switch to have three-layer functions, and VLANs can communicate with each other within the switch without the need to deploy additional routers. This not only reduces hardware costs but also reduces maintenance costs.

2. Simplify network structure and management

By using SVI, VLANs can communicate directly without needing additional external devices, thereby reducing the complexity of the network structure. In addition, SVI can centrally manage and configure the IP addresses and routing rules of all VLANs without the need to manage them on multiple devices, which greatly reduces the burden on network administrators and avoids the risk of errors caused by configuring multiple devices.

3. Lower latency

Since SVI supports the switch to handle routing between VLANs internally, data packets do not need to be transmitted through external devices, which greatly reduces the overall network latency and improves network performance. SVI can also achieve line-speed routing on high-performance switches, which can fully utilize the switch hardware performance and provide a higher bandwidth and low-latency network experience.

4. Improve the flexibility and scalability of the network

In data centers and cloud computing environments, SVI can effectively support virtualized workloads, allowing more efficient communication and resource sharing between virtual machines. And through SVI, VLANs can be flexibly added or deleted, and routing rules between VLANs can be adjusted, so that the network can adapt to changing business needs.

How to Configure SVI on a Switch

Configuring SVI on a switch is relatively simple. The following is an SVI configuration based on Cisco IOS for your reference:

Step 1: Create a VLAN

Before configuring SVI, you need to create a VLAN first, for example:

Switch(config)# vlan 10

Switch(config-vlan)# name DATA

Switch(config-vlan)# exit

 

Step 2: Configure the SVI interface

After creating VLAN 10, we need to create an SVI interface for it and configure the IP address:

Switch(config)# interface vlan 10

Switch(config-if)# ip address 192.168.10.1 255.255.255.0

Switch(config-if)# no shutdown

Switch(config-if)# exit

 

Step 3: Assign switch ports to VLANs

Assign the switch ports that need VLAN 10 to the VLAN, for example:

Switch(config)# interface FastEthernet0/1

Switch(config-if)# switchport mode access

Switch(config-if)# switchport access vlan 10

Switch(config-if)# exit

 

Step 4: Verification

After configuration, you need to use the following commands to verify the configuration of VLAN and SVI:

Switch# show vlan brief

Switch# show ip interface brief

The above are the complete steps for configuring SVI. Configuring SVI mainly includes creating VLAN, configuring the VLAN SVI interface, and allocating switch ports.

Conclusion

As a part of network management, SVI has made outstanding contributions to simplifying network management and realizing VLAN communication within switches. By using SVI, not only can hardware costs be reduced, but also subsequent operation and maintenance costs can be reduced. If you have any questions about SVI or how to configure SVI, please feel free to please feel free to contact QSFPTEK's CCIE/HCIE engineers at [email protected]. Our engineers will provide you with comprehensive support.