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diff between "int vlan+sw port" and "int" on 3750/7609


What is the difference in performance, stability, etc, between a point to point connexion between a 3750 - 7609, 3750 - 3750, 7609 - 7609 with :

interface GigabitEthernet1/0/4

switchport access vlan 806

switchport mode access

interface Vlan806

ip address 1.1.x.x.255.255.252

and the same on the other end

and with this config

interface GigabitEthernet1/0/4

no switchport

ip address 1.1.x.x.255.255.252

for me it's simplier to read the last config than the first, also I tested the last config on a 3550, but I presume it works on 3750 and 7609 also.




Re: diff between "int vlan+sw port" and "int" on 3750/7609

There are different ways to configure a routed port.

In first case, you have created Layer 3 SVI 806 and assigned IP to it. Then instead of assigning IP to Gi1/0/4, you have configured Gi1/0/4 to become member of VLAN 806.

In second case, you have assigned IP directly to the Gi1/0/4 interface.

Both cases serves the same purpose to configure routed port with IP address.

I feel there will not be any difference in performance, stability, etc in both cases.

hope it helps ... rate if it does ....

Community Member

Re: diff between "int vlan+sw port" and "int" on 3750/7609

thanks for your answer, but it seems that i didn't made myself clear, i know what the configs are doing, but i was wandering from constructions point of view, resource utilisations etc etc. If i do a 48 SVI or 48 routed port on a 3750, and full duplex, is the switch going down or not :-)

happy new year


Re: diff between "int vlan+sw port" and "int" on 3750/7609

They are the same thing just a different way of doing things . The SVI definition way allows you to put multiple ports into that same vlan if that is what your network design dictates . Otherwise it does the same thing .

Re: diff between "int vlan+sw port" and "int" on 3750/7609

Hi Ciprian,

There is a difference the way both the connection works. Although they will have the same purpose but there is the difference the way the switch ports will work.

In case of a SVI you will have eventually a Layer-2 link between the switches. This will run your normal STP and other control traffic between the switches.This will extend your STP domain from a switch to the other switch.The ports will go thorugh the normal STP states and in case of a link flap or link going dowm/coming back the recovery time will be a little high.

In case of a routed port between the switches,you will have a layer 3 link between the switches and will work as a normal router port. There will no STP running on the ports and the STP domain will not be extended beyond the downstream switches.Applring layer3 features like ACL's,PBR's will be a ltille easy in this case.

The Disadvantage of running routed ports is that each port will be a separate network and you will have to manage a large number of IP subnets on the network. Running a routing protocol will be a good idea in this case.

My suggestion for running a point-point link between 2 layer3 device would always be a layer-3 link. But this also depends on the kind of network topology you have.

HTH, Please rate if it does.

-amit singh

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