connecting 6509 to a 3550 vlan/switching

Answered Question
Sep 21st, 2010
User Badges:

I am connecting a 6509(10.x.x.x network) to a 3550(192.168.x.x network).  I enabled ip routing.  What else would I need to do to have the 2 switches communicate with each other, and other end devices  too?


Also on the 3550, all the porst besides fa0/1 are configured to vlan 187.   Ports fa0/1 on both switches are set to trunks and both switches are connected through fa0/1.

Correct Answer by Jon Marshall about 6 years 7 months ago

ajmadriaga wrote:



It would be the first option.  I changed port fa0/1 back to regular ports.  I added vlan188 which is a /30 network to connect the switches together(192.168.190.1,2). 1 being on the 6509, and 2 being on the 3550.


I also added static routes to both switches:

6509: ip route 192.168.0.0 255.255.0.0 192.168.190.2

3550: ip route 0.0.0.0 0.0.0.0 192.168.190.1


Also plugged in a laptop to the 3550switch and configured the ip address to 192.168.187.43 and the default gateway to 192.168.190.2.

My Desktop is on the 6509 switch with an ip address of 10.5.100.5 and a default gateway of 10.5.1.1.


I am still unable to communicate with the laptop.


Laptop default-gateway should not be 192.168.190.2 it should be the IP address assigned to the L3 vlan interface on the 3550 for the laptop vlan ie. it will be a 192.168.187.x address.


This only works if you are routing the 192.168.187.x subnet off the 3550.


As an aside if you are simply wanting a routed connection between the 2 switches which it sounds like you do then rather than use a dedicated vlan just make the 2 ports routed ports eg.


6509

====


int fa0/1

no switchport

ip address 192.168.190.1


3550

====


int fa0/1

no switchport

ip address 192.168.190.2


it would still work your way but you are extending L2 between the 2 switches and you don't need to if each switch is routing it's own vlans.


Jon

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4 (2 ratings)
Loading.
Collin Clark Tue, 09/21/2010 - 10:23
User Badges:
  • Purple, 4500 points or more

You will need a common network for the switches to communicate with each other and either static routes or a routing protocol. Let us know if you need more specific help.


10.x.x.x network--192.168.255.1~~~192.168.255.2--192.168.x.x network

Collin Clark Tue, 09/21/2010 - 10:25
User Badges:
  • Purple, 4500 points or more

In your last paragraph do you mean that the 2 switches are already connected via a trunk?

ajmadriaga Tue, 09/21/2010 - 10:29
User Badges:

Yes, on both the 6509 and 3550, port fa0/1 are configured as trunks.  Both switches are physically connected through port fa0/1.

Jon Marshall Tue, 09/21/2010 - 10:28
User Badges:
  • Super Blue, 32500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

ajmadriaga wrote:


I am connecting a 6509(10.x.x.x network) to a 3550(192.168.x.x network).  I enabled ip routing.  What else would I need to do to have the 2 switches communicate with each other, and other end devices  too?


Also on the 3550, all the porst besides fa0/1 are configured to vlan 187.   Ports fa0/1 on both switches are set to trunks and both switches are connected through fa0/1.


Andrew


So the 6500 and 3550 are connected via a trunk link on ports fa0/1 ?


And where have you enabled "ip routing" ? on both switches or just the 6500 ?


If you enable ip routing on both switch and are routung vlan 187 on the 3550 then as Collin says you need a common vlan between the 6500 and the 3550 to send the traffic to the 6500. And you don't need the link to be a trunk link. It can simply be a routed connection between the 2 switches.


If you just enable ip routing on the 6500 and route all vlans on there then the trunk should take care of everything else. Make sure you set the default-gateway of the clients in vlan 187 to be the ip address you assign to the vlan 187 interface on the 6500.


Perhaps you could clarify which one it is ?


Jon

ajmadriaga Tue, 09/21/2010 - 11:06
User Badges:

jon.marshall wrote:


ajmadriaga wrote:


I am connecting a 6509(10.x.x.x network) to a 3550(192.168.x.x network).  I enabled ip routing.  What else would I need to do to have the 2 switches communicate with each other, and other end devices  too?


Also on the 3550, all the porst besides fa0/1 are configured to vlan 187.   Ports fa0/1 on both switches are set to trunks and both switches are connected through fa0/1.


Andrew


So the 6500 and 3550 are connected via a trunk link on ports fa0/1 ?


And where have you enabled "ip routing" ? on both switches or just the 6500 ?


If you enable ip routing on both switch and are routung vlan 187 on the 3550 then as Collin says you need a common vlan between the 6500 and the 3550 to send the traffic to the 6500. And you don't need the link to be a trunk link. It can simply be a routed connection between the 2 switches.


If you just enable ip routing on the 6500 and route all vlans on there then the trunk should take care of everything else. Make sure you set the default-gateway of the clients in vlan 187 to be the ip address you assign to the vlan 187 interface on the 6500.


Perhaps you could clarify which one it is ?


Jon


It would be the first option.  I changed port fa0/1 back to regular ports.  I added vlan188 which is a /30 network to connect the switches together(192.168.190.1,2). 1 being on the 6509, and 2 being on the 3550.


I also added static routes to both switches:

6509: ip route 192.168.0.0 255.255.0.0 192.168.190.2

3550: ip route 0.0.0.0 0.0.0.0 192.168.190.1


Also plugged in a laptop to the 3550switch and configured the ip address to 192.168.187.43 and the default gateway to 192.168.190.2.

My Desktop is on the 6509 switch with an ip address of 10.5.100.5 and a default gateway of 10.5.1.1.


I am still unable to communicate with the laptop.

Correct Answer
Jon Marshall Tue, 09/21/2010 - 11:16
User Badges:
  • Super Blue, 32500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

ajmadriaga wrote:



It would be the first option.  I changed port fa0/1 back to regular ports.  I added vlan188 which is a /30 network to connect the switches together(192.168.190.1,2). 1 being on the 6509, and 2 being on the 3550.


I also added static routes to both switches:

6509: ip route 192.168.0.0 255.255.0.0 192.168.190.2

3550: ip route 0.0.0.0 0.0.0.0 192.168.190.1


Also plugged in a laptop to the 3550switch and configured the ip address to 192.168.187.43 and the default gateway to 192.168.190.2.

My Desktop is on the 6509 switch with an ip address of 10.5.100.5 and a default gateway of 10.5.1.1.


I am still unable to communicate with the laptop.


Laptop default-gateway should not be 192.168.190.2 it should be the IP address assigned to the L3 vlan interface on the 3550 for the laptop vlan ie. it will be a 192.168.187.x address.


This only works if you are routing the 192.168.187.x subnet off the 3550.


As an aside if you are simply wanting a routed connection between the 2 switches which it sounds like you do then rather than use a dedicated vlan just make the 2 ports routed ports eg.


6509

====


int fa0/1

no switchport

ip address 192.168.190.1


3550

====


int fa0/1

no switchport

ip address 192.168.190.2


it would still work your way but you are extending L2 between the 2 switches and you don't need to if each switch is routing it's own vlans.


Jon

ajmadriaga Tue, 09/21/2010 - 11:25
User Badges:

jon.marshall wrote:


ajmadriaga wrote:



It would be the first option.  I changed port fa0/1 back to regular ports.  I added vlan188 which is a /30 network to connect the switches together(192.168.190.1,2). 1 being on the 6509, and 2 being on the 3550.


I also added static routes to both switches:

6509: ip route 192.168.0.0 255.255.0.0 192.168.190.2

3550: ip route 0.0.0.0 0.0.0.0 192.168.190.1


Also plugged in a laptop to the 3550switch and configured the ip address to 192.168.187.43 and the default gateway to 192.168.190.2.

My Desktop is on the 6509 switch with an ip address of 10.5.100.5 and a default gateway of 10.5.1.1.


I am still unable to communicate with the laptop.


Laptop default-gateway should not be 192.168.190.2 it should be the IP address assigned to the L3 vlan interface on the 3550 for the laptop vlan ie. it will be a 192.168.187.x address.


This only works if you are routing the 192.168.187.x subnet off the 3550.


As an aside if you are simply wanting a routed connection between the 2 switches which it sounds like you do then rather than use a dedicated vlan just make the 2 ports routed ports eg.


6509

====


int fa0/1

no switchport

ip address 192.168.190.1


3550

====


int fa0/1

no switchport

ip address 192.168.190.2


it would still work your way but you are extending L2 between the 2 switches and you don't need to if each switch is routing it's own vlans.


Jon


If I just do a routed connection just like your example.  Will that seperate all broadcasts between the 10.x.x.x network and the 192.168.x.x network?  If I were to add a DHCP server on the 192.168 network, will it distribute ip addresses on the 10.x network?


You are also right, each switch is routing its own vlans, I just wanted to have connection to the 192 network from my desktop.

Jon Marshall Tue, 09/21/2010 - 11:30
User Badges:
  • Super Blue, 32500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN


If I just do a routed connection just like your example.  Will that seperate all broadcasts between the 10.x.x.x network and the 192.168.x.x network?  If I were to add a DHCP server on the 192.168 network, will it distribute ip addresses on the 10.x network?


You are also right, each switch is routing its own vlans, I just wanted to have connection to the 192 network from my desktop.


Yes there will be no broadcasts between the switches apart from arp obviously.


If you add DHCP to any vlan and you want other vlans to use this DHCP server then you simply add ip helper-addresses under the other vlans L3 interfaces ie. if your DHCP server was 192.168.5.10 and you wanted to hand out IPs to vlan 10 with an IP subnet of 10.10.10.0/24 then under vlan 10 L3 vlan interface -


int vlan 10

ip helper-address 192.168.5.10


Jon

ajmadriaga Tue, 09/21/2010 - 11:45
User Badges:

I actually got both methods running, using the vlan as a connection.  Also just adding the ip addresses to ports fa0/1.


Thank you very much Jon.

ajmadriaga Thu, 09/23/2010 - 12:23
User Badges:

The two switches are configured with example setup Jon gave me.


I am having another problem.  A desktop assigned to vlan 105 on the 6905 is trying to communicate to a laptop on vlan 187 on the 3550.  Vlan 187 on the 3550 has an IP address assigned to it.  I wanted both switches to be configured so that any vlan on any side of the switch can communicate with each other.


Is there any way to trunk both ports and not use IP addesses on the vlans?

Jon Marshall Thu, 09/23/2010 - 12:29
User Badges:
  • Super Blue, 32500 points or more
  • Hall of Fame,

    Founding Member

  • Cisco Designated VIP,

    2017 LAN, WAN

ajmadriaga wrote:


The two switches are configured with example setup Jon gave me.


I am having another problem.  A desktop assigned to vlan 105 on the 6905 is trying to communicate to a laptop on vlan 187 on the 3550.  Vlan 187 on the 3550 has an IP address assigned to it.  I wanted both switches to be configured so that any vlan on any side of the switch can communicate with each other.


Is there any way to trunk both ports and not use IP addesses on the vlans?


Andrew


Not sure what you mean here. Is vlan 105 routed on the 6500 ? If so it should just be able to route across the link to the 3550 vlan 187.


Obviously you need the 6500 to have a route for vlan 187 and the 3550 to have a route for vlan 105.


Do you have these routes ? if not you can use statics or you can simply run a dynamic routing protocol between the 2 switches suchas EIGRP which if you have a lot of vlans i would recommend.


If i have misunderstood please clarify.


Jon

Actions

This Discussion