GSM7312 - Is there any way to set it to be a Layer 2 switch rather than a Layer 3 switch?

[ctav01]

I did a factory reset and it seems to default to a router setup (show run includes "router rip" and "router ospf" lines).  I just want to use it as a simple Layer 2 switch but it looks like there's more involved than just using EZConfig to set passwords and an IP address.  Any suggestions?

[JohnRo]

Hello ctav01, 

Welcome to the community! 

Regarding your question, the GSM7312 is a fully manageable layer 3 switch - it cannot be bypassed (cannot be compare to a layer 2+ switch which can be used as a plug and play switch); However, For it to function like a layer 2 switch, all you need to do is to assign it an IP address with the same subnet as your existing network. You may follow the installation guide  as it mentions on how to assign an IP or how the switch can get its IP from your DHCP server. Once you have assigned an IP to the switch, it should perform like a layer 2 switch for as long as you do not configure any other settings. 

You can also check out our unmanageable series switches if you consider buying one in the near future. 

Hope this helps! I'll look forward to your reply. 

Thanks, 

[ctav01]

Thanks John.

I went through EZConfig and set an IP which seemed to work.  I can access it via telnet and the web interface while I'm in the same subnet but I get no response when I try to communicate with it from a different subnet.  I'm guessing there's some routing info that needs to be set on the 7312 but I'm not sure where.  Suggestions?

[JohnRo]

Hi ctav01, 

Now, this is where it gets a little complicated. For you to access the switch with another subnet you will have to create a route from the VLAN accessign it or change the management VLAN. This image below is an example of VLANs being routed using a layer 3 switch: 

If you want to get the details, please click here.

Hope this information will enlighten you, if you have more questions I suggest posting a diagram. 

Thanks, 

[ctav01]

Thanks again John.

We actually have a pretty flat network.  Each site has it's own VLAN designation from our main office but the sites themselves are all on VLAN 1.  Other switches at this site are accessable from outside, just not this one (btw, as a layer 2 switch, it works fine on site but it was missed in our network survey so we haven't tried to configure it or monitor it until now) so it must be some setting on the switch that makes it unreachable.  I'm still thinking it's a routing issue but I'm not sure where to look.

Does it make any difference that while I was able to assign an IP to it (and use it while on site), when I go to the web interface on the status page, it shows 0.0.0.0 for the IP?

[ctav01]

If I'm reading the manuals correctly, routing is disabled by default but, after a factory reset, a "show run" command shows "ip routing".  That implies to me that routing is enabled.  I tried "no ip routing" but I lost all access to the switch so I'll have to console in again to do another reset.

I'm also looking at the "network parms" command to set the switch ip address.  The manual has a note saying "The IP address assigned to network in the above table will not be routable. If access to management CPU via the routable interface is desired, use the ip command." so should I be trying to set the switch IP address via the ip command?

[JohnRo]

Hello ctav01,

Do you have the swicth connected to a router? For it work just like a layer 2 switch, all you need to do is to assign it an IP address, subnet mask and a gateway address (from your DHCP server). What firmware version are you using by the way?

I'll look forward to your response.

Thanks,  

[ctav01]

The switch is connected to a router.  I need it to have a static IP address so I can monitor it.  I can try setting it via DHCP but since the switch has problems with anything not on the same subnet (I can't ping the switch from another subnet and I can't ping FROM the switch to another subnet), like our DHCP server, I doubt it will work.

The software version is 6.2.0.14.

Let me ask this, the manual says that the factory default is a Layer 2 switch and you need to specifically enable routing, correct?  So is the running-config supposed to have "ip routing", "router ospf", "router rip" and other routing-type lines after a "clear config" and "reload"?

Also, the running-config has:

interface vlan 1
routing
ip address w.x.y.z netmask
exit

if that makes a difference.

Thanks again.

[JohnRo]

Hi ctav01, 

I get what you mean, for that you will need to configure a management IP on the switch for you to be able to monitor it. Regarding your question about having "IP routing", "router ospf", etc. on default factory mode, yes it does have that. You can refer to the CLI sheet here, pages 42-44. For the issue you are having regarding connecting on other subnets, please follow this guide. 

Hope that helps, I'll look forward to your response. 

Thanks, 

[Jedi_Exile]

Hope this either confuses you or clarifies it

There is network params and then there is vlan 1 routing interface.  Network parms configure the management vlan with IP address and that is what shows up in the Web UI as the IP address.  By default the management vlan is 1 but that can be changed.   The switch UI is also accessible via routing interface (router on stick) configured on any vlan including vlan 1 (default management vlan) but you can't have 2 interfaces on vlan 1.  Either parms or routing interface.  pick one.  The preferred method is routing interface incase you want to later setup vlan routing.

So with above in mind.  You will have either have newer method and UI will show no ip address in management interface

network protocol none
y
vlan database
vlan routing 1
exit
config
interface vlan 1
ip address <switch_ip> <subnetmask>
exit
ip routing
! will add lines like router rip and router ospf if you have L3 switch but no worries
ip route default <gateway ip>
ip name server <dns ip>

OR if you you use DHCP to acquire IP then vlan 1 interface will be DHCP and not static IP above

interface vlan 1
ip address dhcp
exit

Or you can configure the IP in the management interface which means you can't configure vlan 1 with routing interface if you leave the management interface a default vlan 1 (which is what it is by default)

network protocol dhcp

or static IP will be network parms or network parameters

network parms <ip address> <subnetmas> <gateway_ip>

It does not really matter though since in the end you are just creating a interface to reach the switch.  Both method will make the switch accessible from anywhere.  It just depends on what you want to achieve.  Or be bit more crazy and do this

network protocol none
y
network parms 192.168.200.254 255.255.255.0
vlan database
vlan 2048
vlan name 2048 "My spare mgmt vlan"
vlan routing 1
exit
network mgmt_vlan 2048
config
interface vlan 1
ip address 192.168.1.254 255.255.255.0
exit
ip routing
ip route default 192.168.1.1
ip name server 8.8.8.8
interface 0/1
vlan participation include 2048
description "Spare port for management access for 200.254"
exit