IP Configuration
Overview
270 Cisco Small Business 200, 300 and 500 Series Managed Switch Administration Guide (Internal Version) 
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• If the IP address on the device is changed, the device issues gratuitous ARP 
packets to the corresponding VLAN to check IP address collisions. This rule 
also applies when the device reverts to the default IP address.
• The system status LED changes to solid green when a new unique IP 
address is received from the DHCP server. If a static IP address has been 
set, the system status LED also changes to solid green. The LED flashes 
when the device is acquiring an IP address and is currently using the factory 
default IP address 192.168.1.254.
• The same rules apply when a client must renew the lease, prior to its 
expiration date through a DHCPREQUEST message.
• With factory default settings, when no statically-defined or DHCP-acquired 
IP address is available, the default IP address is used. When the other IP 
addresses become available, the addresses are automatically used. The 
default IP address is always on the management VLAN.
Layer 3 IP Addressing
In Layer 3 system mode, the device can have multiple IP addresses. Each IP 
address can be assigned to specified ports, LAGs, or VLANs. These IP addresses 
are configured in the IPv4 Interface and IPv6 Interfaces pages in Layer 3 system 
mode. This provides more network flexibility than the Layer 2 system mode, in 
which only a single IP address can be configured. Operating in Layer 3 system 
mode, the device can be reached at all its IP addresses from the corresponding 
interfaces. 
A predefined, default route is not provided in Layer 3 system mode. To remotely 
manage the device, a default route must be defined. All DHCP-assigned default 
gateways are stored as default routes. In addition, you can manually define default 
routes. This is defined in the IPv4 Static Routes and IPv6 Routes pages.
All the IP addresses configured or assigned to the device are referred to as 
Management IP addresses in this guide.
If the pages for Layer 2 and Layer 3 are different, both versions are displayed.