SG300-28P & Modem setup

[lkhsu3275]

Hi,

   I am petty rookie, and still learning everything.

We are changing internet provider to comcast now. Our previous provider provide DHCP server but comcast. I am able to setup the DHCP server on SG300 now, but when I connect it to the cable modem. The DHCP server seems work, but no PCs can connect internet. I have the comcast ip/gateway/sub info, but where I should put in SG300? 

Thank you very much. 

[Brandon Svec]

Did you leave your Comcast in default state or put it in bridged mode?  In my experience, by default the Comcast modem will do DHCP and NAT, etc. so all you should have to do is plug the internet port into a switch port and no configuration on the SG is necessary for basic operation.

If you are not sure just plug a computer into the internet port on the Comcast modem with nothing else connected and check your network setting to see what IP, subnet, gateway and DNS you see and report back.

[lkhsu3275]

This is a Business line, so they give us Cisco DPC3008 modem, which no DHCP server and need to connect a L3 router. They did give me the IP/Gateway/Sub, but not sure where to enter in SG300.

I used Laptop to connect the modem, and I need to enter IP/GW/Sub manually to go online.

[Brandon Svec · Accepted solution]

I see.  I don't think you can make this work without providing a firewall or router between the switch and Comcast then.

You *might* be able to do something with the switch in layer 3 mode, but I suspect it does not handle NAT and would not be a good solution to run your network without a firewall anyway.  How many users do you have?  I can suggest looking at Cisco Meraki line of firewalls.  They are very good, easy to manage and have great support.

Good luck.

[lkhsu3275]

Thank you, understand now.

Is any other suggest model? Meraki is wireless ap, too. Is any no wireless model?

Our office is about 40 IPs. 

[Brandon Svec]

Meraki got famous for wireless, but also makes firewalls and switches.  Their MX64 sounds about right for that size.  Here is a link to their sizing guide: https://meraki.cisco.com/lib/pdf/meraki_whitepaper_mx_sizing_guide.pdf

[lkhsu3275]

Ok, another question. 

About the license "new release update", is that mean if I don't buy the license, it's no future update even there is a new firmware? Or just security definition update? 

[Brandon Svec]

Meraki is an "all or nothing" proposition.  You have two choices for licenses on the MX firewalls, enterprise or advanced.  Advanced includes the IDS/IPS subscriptions and content filtering.  All licenses include updates, 24/7 phone support, lifetime hardware warranty.  Buying 3-5 or even more years in advance is discounted greatly.  Meraki is not a fit for everyone, but if you consider what you get for the money, it is a good value in my opinion.

For example, a MX64 with 3 year advanced security license is about $1250 USD.  Or about $35 per month.

I suggest checking out some of their webinars or youtube videos.  They also give away free APs and switches for attending.

Of course if this is totally out of your budget and not what you need you can just go get a $50 router from the store nearby :)