I have a network with 3x SG300-52p switches and 3x SG300-28PP switches.  All are set as L3 even though I only wound up using them as L2.  I have a VPN set up in my firewall and I'm able to connect in.  From my VPN connection I'm able to connect to the 3x SG300-28PP switches but not to my 3x SG300-52p switches. On the SG300-28PP switches I go to: -Administration ---Management Interface -----IPv4 Interface and I have: -Management VLAN:  10 -IP Address:  172.16.x.x -Network Mask:  (The mask) -Administrative Default Gateway:  User Defined:  172.16.x.x Adding in that Default Gateway allows me to connect across the subnets / VLANs.   I'm fairly certain this is a Gateway issue on the SG300-52p switches.  Under: -IP Configuration ---IPv4 Management and Interface -----IPv4 Interface I have: -Interface:  VLAN10 (the data VLAN and also the VLAN that the switches reside on for us to log in and maintain) -IP Address Type:  Static -IP Address:  (The 172.16.x.x IP of the switch) -Mask:  (The Subnet mask) -Status:  Valid There is no place for the "Administrative Default Gateway".  The only place I can see that may be for that is IPv4 Routes.  What do I need to set to enable the packets to route of the subnet.  I'm concerned that if I set an IPv4 Route that I'll mess something up.  Thanks for any advice! ... View more

We have a network of 6 switches and are adding a 7th.  5 of the existing 6 are SG300 units and 1 is an old L3 Catalyst which is currently the gateway.  We tried to add another SG300-52P today but whenever we plug it in, the rest of the switches stop communicating with each other.  (The #'s are our way of identifying the switches).  The intent is to add this new switch for capacity and then eventually migrate away from the Catalyst.  We use VLAN2 for voice and VLAN10 for data.  This is how they all currently link together:   Catalyst_#3 <--Ethernet--> SG300_52P_#4 <--Fiber Link via FMC--> SG300_26P_#7 <--Fiber Link--> SG300_26P_#8 | |-<--Ethernet--> SG300_52P_#5 <--Fiber Link--> SG300_26P_#9   The new switch an SG300_52P_#6 plugging into SG300_52P_#5.  Ports on each switch are configured as 2T, 10T, 4095P.  Everything is running fine inside of the network but the moment we plug the new #6 switch into the existing #5 switch it all just kind of falls apart and packets start dropping.  Once we unplug it comes back after about 10 seconds.   More info: 1.  All switches are configured as Layer3 but only the Catalyst has any routes configured.  The others are only configured as such in case the Catalyst goes down and we need to do some configuring on one of them to get the network back up.  Since changing them from L2 to L3 wipes the config it seemed like a good idea. 2.  I've read that the best way to interconnect the switches is to tag all the VLANs and leave VLAN1 excluded.  Some of our switches are interconnected with that config.  Some are interconnected with the VLANs tagged except VLAN1 is untagged.  Not sure why we did that.  3. We haven't configured any other protocols such as STP. 4.  We have verified that the IP assigned to the new switch works just fine.   Any help would be appreciated.  Just when I think I've got the whole VLAN thing figured out something like this pops up and makes me realize there must still be some things I don't quite get. ... View more