Question Regarding Management Ports

[ohanquels]

I purchased a refurbished WS-C3750E-48PD 48 port PoE gigabit switch for $170 with a 1 year warranty. It has the latest IOS version of 12.2(55)SE12 running image C3759-UNIVERSALK9-M.

When I first got it and fired it up with a console cable attached it started the new switch setup in cli. Now this thing is Stack Aware and really built for that but I will only be using it as a single switch attached to a Firewalla Gold and some Netgear Nighthawk APs. One is an old router and I know it has a VLAN mode. My main use case is going to be segmenting my IoT network and Camera network to separate VLANs than my priority network. Just wanted to make everything clear before I go into my question and what I’m wanting to do.

Now In the cli setup Wizard it asks what interface you want to use as a management interface. Since it has a 10/100 Management interface on the back next to the console port, I just naturally selected that port. But I got to thinking that I’m not going to be building a separate management network. And I don’t want to plug that into a gigabit interface and create a loop. So would it be better to reconfigure the management interface to be one of the front gigabit ports, that way I can access it from my main network for management? The main reason I don’t want to use the one on the back is that it’s 10/100 and I’d like to not have anything slower than gigabit in the setup. So if it would be best to change the management interface to say gigabit Ethernet port 1 and then just not have anything plugged in there? In the past when I was configuring Cisco switches they were always in a stack and the smaller client end switches were managed based on that subnet block.

I feel like I’m over complicating things but I just want to be able to manage the switch from the primary network either by ssh or web interface. Still trying to find my copy of Cisco Network Assistant and use it to setup LACP and such since it’s just easier. Thanks in advance and SSL.

[balaji.bandi]

Sure you only need the Management port separate if you have  OOB (that is most used of enterprise Lan)

if you have only one device, you use any VLAN inside LAN can manage this switch. Make a Small diagram of what you looking to do, so we can suggest doing, is this Switch you looking for Layer 2 or Layer3?

[Flavio Miranda]

Hi

 You not over complicating, this is a pretty legitime question. No one use mgmt port either. What you can do is create a loopback for management:

int loopback 1

ip add 192.168.1.1 255.255.255.0

Then, you create a route to you Lauer 3 device

ip route 0.0.0.0 0.0.0.0 "gatewat"

What people often do is use some interface vlan.

int vlan 10

ip add 192.168.1.1 255.255.255.0

Then, you can add the vlan 10 on the trunk to the core.

[Richard Burts]

Given that this is a 3750 switch I am little puzzled by the suggestion to configure a loopback interface. 

It is not clear to me whether the original poster intends to do IP routing on this switch or whether this switch is intended to operate as just a layer 2 switch. If the switch will operate as layer 3 switch and route between the vlans then the switch will have a layer 3 vlan interface for each of the vlans. You simply use one of those vlans interfaces as your management interface. If the switch will operate as layer 2 and routing will be done on some other device then you should configure a vlan interface for one of the vlans (does not matter which one), configure an IP address for that vlan interface and that vlan interface will function as your management interface.

There is a statement in the original post that relates to this "So if it would be best to change the management interface to say gigabit Ethernet port 1 and then just not have anything plugged in there?" You do not need to identify a physical port for the management interface. For the management interface of the switch all you need is a layer 3 interface with an IP address that is reachable from the other parts of the network.