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How to configure two Core switches in a network with intervlan routing ?

Dear All,

               Hi Friends, i have two 3750 switches. I configured intervlan routing between three vlans which are vlan11,vlan12, and vlan13 in Core Switch1. These three vlans are communicate each other as vice versa. Now i am going to implement another Core 3750 switch in below the Core switch1 for some storage purpose.


               My question is, i want to configure another vlan(ie: vlan300) for storage in Core switch 2. and i have to communicate with all vlans which is in Core switch1. Is it possible, if so what is the procedure to do so? Can i get configuration CLI commands?



                Note: Why i thought to go for one more Core switch is, for Good throughput. This Vlan300 is for storage servers. I want perfect throughput without any drops thats the reason i go for one more Core Switch. 


                Please help me or advice me the good suggestions. Advance in Thanks.


Thanks and regards,




Thanks and regards, Chandhuru.M

HelloOn the core switch 1


On the core switch 1 create another svi L3 interface for vlan 300 and l2 vlan 300

Also on the physical interface connecting the new 3750 configure that as a trunk interface


Config t

Vlan 300


Int vlan 300

IP address x.x.x.x y.y.y.y

Int xxx 

Description new switch

Switchport trunk encap dot1q

Swichport mode trunk

No shut

Sh vtp status


New switch;

Config t

No ip routing

Int vlan xxx

Description Management vlan

Ip address x.x.x.x y.y.y.y

Ip default-gateway x.x.x.x (IP address of core 1 svi for management vlan)


Int x/x

Description physical link to core1

Switchport trunk encap dot1q

Switchport mode trunk

No shut

vtp domain (same as core 1)


Int x/x

Switchport host

Switchport access vlan 300

No shut


Res Paul

Please don't forget to rate any posts that have been helpful. Thanks.

Hi Paul,Thanks for your kind

Hi Paul,

Thanks for your kind reply. I have few more queries. 

 interface Vlan2
 description ####SWITCH_MANAGEMENT####
 ip address
 standby 1 ip
 standby 1 priority 120
 standby 1 preempt


This is my Core 1 Management Vlan and IP. I have to mention as ip default gateway in Core2 is in did?


Then if i do as you said, can i get full throughput. Are you sure on it, will not get any drops in throughput?


One more query is, can i configure any vlan in Core2 and do intervlan between all those vlans which is in core1?

Advance in thanks.


Thanks and regards,


Thanks and regards, Chandhuru.M

Dear Paul,                  I

Dear Paul,

                  I am expecting your reply for my below queries. Please do needful as soon as you can. Takecare.


Advance in thanks






Thanks and regards, Chandhuru.M
New Member

Hi, If the only reason for an



If the only reason for an extra switch is more throughput then you should be stacking the two switches. Cisco 3750 is a stackable switch which will provide you more throughput and resiliency at the same time. Please visit the following link for more info on Catalyst 3750.

If you chose to stack the switches you only need to create vlan 300 on the switch1 same way you created the other vlans and then just assign the ports to all the hosts and storage servers in a redundant fashion.




Dear Khan,                 

Dear Khan,

                   Really thanks for your prompt reply. Link was so useful which you sent. 


                   I can understand what you said about stacking. Really i impressed. But my small query is only stacking is possible to improve Throughput or any other method to do good.


                    Advance in thanks.





Thanks and regards, Chandhuru.M
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