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vlan routing on SG300-28P



ASA5505    ------------     SG300-1    ------------   SG300-2                          |

                                            +---------------------   SG300-3


                                            +---------------------   SG300-4




                                            +____________   two Dell PowerConnect switches on and .31    (Windows servers & computers)

SG300-1  is in layer 3 mode

     vlan1 (default)

     vlan100 (voice)

     vlan100 dhcp server on the network

     Auto voice vlan set to 100

SG300-2,3,4 are all in layer 2 mode


The phones plugged into SG300-4 have PC's plugged into them. The phones and pc's all fire up fine just like it is supposed to work. The phones all come up on network and pc's are on the network. Magic!!

The phones plugged into the SG300-1 switch all come up just fine on the .100 network. No pc's on this switch.

The phones plugged into the SG300-2 and -3 switches can not find an IP address. I can see in the binding list on the SG300-1 switch a bunch of "preallocated" addresses from the mac addresses of those phones but the phone just sits there waiting for an address.

It is as if the dhcp response from the phone never makes it back to SG300-1 to tell it has the address.

Why does SG300-4 work and the other two do not? I have compared configs until I am cross-eyed and swear they are identical.

New Member

vlan routing on SG300-28P

Hm, not even a hint?  OK, well I have it mostly working finally. I say mostly because all of the phones and pc's have now pulled the correct ip's from their proper subnets and and fine. The last issue is from a 192.168.1.x computer I can ping a 192.168.100.x computer but can not access anything on it. One is a web server and even tho I can ping it, does not respond. I did a port scan on it from the .1.x network and it shows all ports closed.

Why can I ping it fine but not access anything on it?

Hall of Fame Super Blue

Re: vlan routing on SG300-28P


Hm, not even a hint?

I suspect no one has helped because this forum deals with Cisco Catalyst switches so there is limited experience with the Small Business switches. There is a dedicated forum for these switches so you could move this thread there and you are far more likely to get help from people who work with these switches -


New Member

vlan routing on SG300-28P

Thanks Jon.marshal. I have moved it as you suggested. When I posted I just did a search and guess I landed on the wrong list.


vlan routing on SG300-28P

Hi Gary, that sounds more like a firewall/security software issue on whatever you're trying to access. If a ping works, it means the routing works.

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