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SG300-28 VLan help with Static/DHCP

Scenario: I would like to be able to have a static block of ports and a dhcp block of ports on the same SG300 switch.

ISP - Business Cable

Cable Modem supplied by ISP has 1 Wan Port.

I have:

Static block of 8 usable IP addresses

Connected directly to this modem, I have unlimited DHCP addresses (the ISP acts as the DHCP server)

As a test, I currently have an auto sensing switch connected directly to the Wan Port on the Modem. From the auto sensing switch, I have a cable connected to the SG300-28 that is configured for the static.  I also have 2 cables connected from the auto sensing switch to laptops, both of which have public dhcp addresses directly from the ISP. All of my devices on the SG300-28 as well as the laptops are connected without issue.

Is there a way that I can assign 8 ports to the static block, and then use the DHCP from the isp for the other ports? I would like to remove the auto sensing switch from this equation and configure the SG300 to connect directly to the Cable Modem.

I believe I need to make the SG300 a Layer 3 switch and configure VLANs in some way.

Can someone provide me some guidance in doing so?


SG300-28 VLan help with Static/DHCP

Hi Matt, the SX300 cannot utilize the public IP addresses from the ISP for your clients to connect because it does not support NAT.

I have the sense that is what you're attempting to do? Have a computer receive a private DHCP address then use the internet like normal like your current set up?

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-Tom Please mark answered for helpful posts
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