RIPv2 / Questions

Hello all! I had a few questions.

I have 3 switches in a triangle. Each switch has vlan(s) that are only local to that device. IE;

Switch 1:
Vlan A

Switch 2:
Vlan B,C

Switch 3:
Vlan D,E

Also, there are some VLans that are common between those switches. I currently have those vlans added to the LAGS between each switch.

My question,

I want Switch 1,3 to know about the networks/VLANS on switch 2 and vise versa.

Now my question, how do I get switch2 to send its networks across the LAG without tagging the VLAN on the LAG? Right now, on switch 2, if I tag VLANS B,C on the LAGs.. then the other switches route tables will show the networks. If I dont tag B,C then the other switches dont know about the networks.

I dont want B,C to be added as a VLAN to any other switch, but I want the other switches to know about it.

Also; will that cause problems for me if one end of the LAG there is added VLANS tagged, but its not reflected on the other end?

IE;
SW1 (Tag A,F,G,H) <---LAG---> SW2 (Tag B,C,F,G,H

Thanks!

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Comments

2URGSE

bigheadx wrote: »

Hello all! I had a few questions.

I have 3 switches in a triangle. Each switch has vlan(s) that are only local to that device. IE;

Switch 1:
Vlan A

Switch 2:
Vlan B,C

Switch 3:
Vlan D,E

Also, there are some VLans that are common between those switches. I currently have those vlans added to the LAGS between each switch.

My question,

I want Switch 1,3 to know about the networks/VLANS on switch 2 and vise versa.

Now my question, how do I get switch2 to send its networks across the LAG without tagging the VLAN on the LAG? Right now, on switch 2, if I tag VLANS B,C on the LAGs.. then the other switches route tables will show the networks. If I dont tag B,C then the other switches dont know about the networks.

I dont want B,C to be added as a VLAN to any other switch, but I want the other switches to know about it.

Also; will that cause problems for me if one end of the LAG there is added VLANS tagged, but its not reflected on the other end?

IE;
SW1 (Tag A,F,G,H) <---LAG---> SW2 (Tag B,C,F,G,H

Thanks!

Not sure if I understand your question to the fullest, but first of all, if you wish the switches to share VLAN's, than you need the following:

* Make sure the ports connecting to the switches are set to trunk mode.

* All switches must be in the same VTP domain. (case sensitive)

* All switches must have the same VTP password. (case sensitive)

* In this case, make sure STP is running, to prevent loops.

* All switches must be running the same VTP version.

Keep in mind the 3 modes of VTP: Server, Client and Transparent. Program your switches according to those modes, depending on what you want to do.

Keep in mind the effects of the configuration revision # on those switches and the VLAN's they will learn, as well as the difference in the modes I described.

wes allen

Edited to add: Not sure what you are asking, either. Do you want IP connectivity from hosts that are on vlan a to hosts vlan d?

Vlans are a layer two concept, IP routing is layer three. So, as long as your switches also support layer three, you just need to set up RIP/OSPF/Static routes, etc. As long as each pair of switches has a common vlan and you setup your routing protocol on that vlan interface, your updates should be propagated out and you should be able to reach the IP address of vlan d,e from vlan a, etc. Just think of each vlan as a logical router interface when you are doing stuff at layer 3.

2URGSE

wes allen wrote: »

Edited to add: Not sure what you are asking, either. Do you want IP connectivity from hosts that are on vlan a to hosts vlan d?

Vlans are a layer two concept, IP routing is layer three. So, as long as your switches also support layer three, you just need to set up RIP/OSPF/Static routes, etc. As long as each pair of switches has a common vlan and you setup your routing protocol on that vlan interface, your updates should be propagated out and you should be able to reach the IP address of vlan d,e from vlan a, etc. Just think of each vlan as a logical router interface when you are doing stuff at layer 3.

It does not sound like they are layer 3 switches, sounds like more of a CCENT or ICND2 type question about VLAN propagation. He does not mention a router either.

wes allen

2URGSE wrote: »

It does not sound like they are layer 3 switches, sounds like more of a CCENT or ICND2 type question about VLAN propagation. He does not mention a router either.

I think what was confusing to me was the use of RIP2 in the thread title and asking about "networks" in the question, thus implying some type of layer 3 involvement. My edit was to ask if he wants connectivity from the hosts on one vlan to the hosts on another one, and if so, then he needs some type of layer three involvement.

bigheadx

Sorry for the confusion. They are L3 switches, and I want IP communication. Basically, I have a LAG setup between all 3 sets of switches. On that LAG, I am tagging my routing vlan. Each switch has an IP address within this routing VLAN.

Then, I add the networks to rip that I want to be routed. That should be it right? I shouldnt have to tag them as well?

Switch1 is in building 1, switch2 in building 2, and switch 3 in building 3. I don't want to trunk VLANS everywhere, so the vlans for each floor in building 2 should only stay on those switches. I'd like the other switches to know how to get there via RIP.

Did that make a bit more sense? Thanks!

wes allen

I think you are correct - enable and config RIP on the switches and the shared vlan interface and you should be good to go. Generally, I just use one L3 switch with all the vlans configured on it, then tagged out to L2 access switches as needed, but I guess it should work fine the way you have it set up.

bigheadx

Thats my dilemma. I'm not sure how to configure my network. Heres the scenario, Building 1 is my "main" building. Its DMARC comes in on the 1st floor, which is where I have a L3 switch and my HA firewalls. That "stack" is the default gateway for each of the floors in the building. IE; Floors 1,2,3 all have L2 unmanaged switches connected to the L3 stack on the 1st floor. So on my L3-1stFloor-Stack, I have the ports conifgured as access, and assigning the VLAN respective to each floor.

Ok, now, our datacenter is in the basement and we have a fiber link running down stairs. There is another L3 stack down there. This is also where the fiber from the new buildings will be pulled in. The current L3 stack is a pair of Dell 6224's. The additional L3 stack is a eXtremenetworks 460/450. Since I'll be running a loop, I decided to go with them and use their EAPS protocol. So there will be a lag between both of those L3 stacks in my datacenter.

From here, the eXtreme-DC stack will have both buildings connecting to it via fiber. I'm trying my best to shrink broadcast domains. I could put each buildings default gateway on the eXtreme-DC stack, but why not just leave it local to the building and use RIP to get my routes, right? All my switches are L3 aside from my closet switches on floors 1,2,3 of my first building.

My plan was to implement my "routing" vlan; trunk it everywhere. Use it to advertise RIP; and for my management. There will also be a couple other vlans that I will trunk across my network; Wireless, Voice, and Video.

Any advice? Suggestions?

I really appreciate it.

wes allen

I am sure there are several ways to set up what you want to do, but I don't know enough to really give you specific advice. I will say that, generally, it seems to me that people worry more about broadcast domains then the issue deserves, so I tend to try to keep designs as simple as I can. Yes, broadcasts take up bandwidth, but with 1gb or 10gb links, is it enough to justify a more complex design with several L3 devices and RIP rather then basic vlan tagging with one L3 core switch? Same with the L2 loop - is it worth the additional complexity to implement, or is a simpler design good enough for your network?