VLAN's and Trunking

[Jeff Harned]

Hello All,

Could use a little help:

What I have is two source devices feeding two separate ports on 3750 switch with each port in separte VLANs. Each source device has its

own IP multicast address assigned to it.  I then set up a single trunk to a 2950 switch in which two ports are set up for the identical VLANs

created in the first switch.  These two ports are connected to two separte destination devices. The trunk works sending the correct multicast data

through each VLAN port on the 2950 switch.

The issue I have is that I also have a third destination device hooked up to the 2950 switch.  I also want to be able to send muticast data to its port

like the other two.  It is my understanding that you can not assign two VLANs to one port.  I would like to be able to use VLANs in my

project but is there a way I can set up this third port to receive multicast data.

Thanks.

Regards,

Jeff

[Richard Burts]

Jeff

Perhaps there is some aspect of your question that I am not understanding correctly. But it seems pretty straightforward that if you put the third destination device into one of the established vlans that it would be able to receive the multicast being sent on that vlan. Is there something that I missed?

HTH

Rick

[Jeff Harned]

Hi Rick,

Thanks for your response. 

I will try to further explain myself.  I have enclosed a version of the block diagram for this project that should help

better explain my question.  The third destination device if possible,  I would also like to keep in a separte VLAN.

The two source devices outputs each a multicast data stream.  Each source port is put as shown in separte VLANs (5 and 10)

and trunked down to the first two destination devices.  All destination units are setup to be able to receive both multicast data streams.

The final goal is to write a script so when executed only when multicast data stream will be broadcast out at a time from each destination unit

into the matrix device................this is later in the process.

The issue that I have now is how do I set up the port to the third destination unit to be able to recieve muticast data?  If I can not put this in its own

VLAN is there another way?

Thanks Rick.

Regards,

Jeff

[paul driver]

Hello Jeff,

Are you able to create another SVI on the 3750 for a new vlan and then create the L2 vlan, making sure the trunks can carry this new vlan and then just assign the 3rd dst device the new vlan?

example:

======

3750

------

int vlan 15

ip address 10.1.15.1 255.255.255.0

vlan 15

exit

2950

===

int x/x

switchport mode access

switcport access vlan 15

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

Thanks.

[Jeff Harned]

Hi pdriver,

I have a  limited knowledge with networking but I am learning and willing to learn more!!
I have no experience with SVI but still want to to use VLANS associated with both Layer 2 and 3 devices.

My latest adventure was working with MVR associated with the 2950 with great success.  This time I

want to use a Layer 3 device (3750) and route the multicast data around using VLANS and trunking to the 2950.

In refernce to my original post I am trying to route two multicast data streams from two source units to three destination

units using VLANS.  The third destination unit is where the issue is at.  How can I get data to it?

If VLANS is not the way to do this, can you suggest another way and I will do research on it?

Thanks.

Regards,

Jeff

[Richard Burts]

Jeff

The SVI is nothing more than the layer 3 interface for a vlan that allows you to route traffic in and out of the VLAN. So interface vlan 5 is the SVI for vlan 5 and interface vlan 10 is the SVI for vlan 10.

If you create a third vlan then create a vlan interface for that vlan and you should be able to route to and from the new vlan.

The answer about how to get multicast to the third vlan is probably that you will do for it what you have done for the two existing vlans which are working. If you run CGMP for them then run it for the new one. If you are running IGMP snooping for them then run it for the new one. If you are using Protocol Independent Multicast for them then use PIM for the new one.

HTH

Rick

[paul driver]

Hello
Okay let's go for creating a layer 3 interface ( svi) on the 3750

Can you post your existing config to we can see what is configured presently

Res
Paul

Sent from Cisco Technical Support iPad App

[Jeff Harned]

Hi Paul,

I do not have much because of my issue.  There are two attached files; one block diagram and the other the configuration steps.
I think my issue is still not clear.  Looking at the data I sent; in summary I am trying to route two VLANs to three separete VLANs.

VLAN 5 data passes through to VLAN 5 created in the 2950 and VLAN 10 data passes to VLAN 10 also created in the 2950.

Since there are only two VLANs created from the two source devices, how can I create a 3rd VLAN for the the 3rd Destination device

and still recieve multicast data from the other two VLANS though there is no 3rd VLAN created on the 3750 switch?

I eventually want to be able to (through a script) to select only one multicast data to pass on through any one of the three destination units

to the matrix device......but again this is at a later time.  First I have to get the corrrect port configurations.

I do not want the answers but some guidance on how to solve my first issue first........I want to learn by being involved in the process!!

Thanks.

Regards,

Jeff

[vishal vyas]

###########3750-config########

!

interface vlan 5

ip address 10.1.1.1 255.255.255.0

!

interface vlan 10

ip address 20.1.1.1 255.255.255.0

!

ip routing

!

interface gigabitethernet1/0/1

switchport mode access

switchport access vlan 5

!

interface gigabitethernet1/0/2

switchport mode access

switchport access vlan 10

!

interface gigabitethernet1/0/5

switchport mode trunk

switchport encapsulation dot1q

!

##########2950-config########

!

interface gigabitethernet1/0/5

switchport mode trunk

switchport encapsulation dot1q

!

interface gigabitethernet1/0/10

switchport mode access

switchport access vlan 5

!

!

interface gigabitethernet1/0/20

switchport mode access

switchport access vlan 5

! ###########3750-config########
!
interface vlan 5
ip address 10.1.1.1 255.255.255.0
!
interface vlan 10
ip address 20.1.1.1 255.255.255.0
!
ip routing
!
interface gigabitethernet1/0/1
switchport mode access
switchport access vlan 5
!
interface gigabitethernet1/0/2
switchport mode access
switchport access vlan 10
!
interface gigabitethernet1/0/5
switchport mode trunk
switchport encapsulation dot1q
!
##########2950-config########
!
interface gigabitethernet1/0/5
switchport mode trunk
switchport encapsulation dot1q
!
interface gigabitethernet1/0/10
switchport mode access
switchport access vlan 5
!
!
interface gigabitethernet1/0/20
switchport mode access
switchport access vlan 5
!

I am not sure what do you mean by multicast traffic, but if you want to run multicast straem than tou need to enable PIM sparse or dence mode

[Richard Burts]

Jeff

Perhaps there has been a failure to communicate effectively, or perhaps I have not correctly understood parts of what you have told us. So let me try to clear up a little bit.

From my perspective the vlans exist on both the 2950 and the 3750 and the 3750 is providing routing logic for the vlans. It can route to vlan 5 and to vlan 10 and can route between vlan 5 and 10. So from this perspective I was assuming that the third vlan would be configured on both the 2950 and the 3750 and the 3750 would have routing logic for the third vlan as well as the two existing vlans.

Without the third vlan on the 3750 I am not sure that you could get it to work.

HTH

Rick

[Jeff Harned]

Hi Rick,

You got it!  I have two VLANs (3750) from two sources trying to feed three destination units also with two

VLANS. I am trying to create a third VLAN (2950) on the third destination unit to also recieve data.

There is no third VLAN from the source since there are only two source units to create VLANs with.

If this can not be done is there another scheme I can take a look at.  Remenber my knowledge base is limited.....

but I want to learn!!

Thanks.

Regards,

Jeff

[Jeff Harned]

Hi Rick,

A follow up:

I was able to get multicast data to the 3rd destination unit!!  I used MVR to reconfigure all ports used on the 3750

& 2950.  The key to this was that I was able to trunk port 5 on both switches using MVR which passed both

multicast data to ports 10,15 & 20 on the 2950.  My next step is to use a script to select which multicast data is

passed through each destination unit.

Any comments on this scheme using MVR would be appreciated!!

Thanks.

Regards,

Jeff

[Richard Burts]

Jess

I am glad that you are making progress in getting it to work.

I am not familiar with MVR and so am not sure that I have much to say about it.

HTH

Rick