2 ex4200 stacks, 2 vlans, 1 powerconnect m6220, won't use both vlans

[jmelcher21]

I have two ex4200 stacks that are on completely different networks for different uses.  One has only a single vlan, 17.  The other has several, but I only want to use vlan 10.  Both of these stacks are connected to a dell m6220 on the back of a n m1000 blade server.  The idea is to have a virtual machine be on both networks.  The m6220 does not route the traffic between the vlans.  The m6220 can ping the stack on vlan 17 perfectly fine, but it can't ping the stack with vlan10.  HOWEVER, if I shutdown the port connecting to the vlan 17 stack, the ping will start working to the vlan 10 stack.  While this might seem like an m6220 question, it isn't.  I hooked another ex4200 to the m6220 instead of the vlan 10 stack.  I gave it very basic configuration.  The m6220 can ping it and see it along with the other stack no problem.  It looks like to me the vlan 10 stack must have some kind of configuration that won't let it send or receive traffic to the m6220 when the other stack is actively communicating with it.  I'd post the config, but it's sensitive information.  Does this situation sound like anything anybody would know about?  Thanks!

[jmelcher21]

By the way, since I'm only using one vlan on both stacks, I'm not using trunks.  I tried using them thinking something about them that is beyond my knowledge might make it work, but same situation.

[jmelcher21]

Here is a little diagram I threw together.  I can ping x.x.x.1 all day long from the m6220 when both are connected.  I can't ping x.x.x.4 though.  If I disconnect x.x.x.1, suddenly pings start flowing through to x.x.x.4.  As soon as I reconnected x.x.x.1, traffic stops to x.x.x.4. 

[nikolay.semov]

is the x.x.x in x.x.x.1 the same as the x.x.x in x.x.x.4? What you describe almost sounds like a routing issue. Do you have just a single subnet?

[jmelcher21]

No sir, they are two fully separate networks.  There is no routing between the two VLANS either.  Other than this single virtual machine, nothing else from either network is to touch the other network.

[nikolay.semov]

Well, if nothing else from either network is to touch the other, then:
- Can your virtual machine reach both networks ok?
- Why are you trying to get the m6220 to reach both networks?
- This still seems like a routing issue, and very much an m6220 question, or a "very basic configuration" question, speaking of which, if production configuration is sensitive, could you post the configuration of the 4200 you used in place of the M6220?

[jmelcher21]

Alright, I have another diagram, this has snippets of my config with generic information put in.  The virtual machine can talk to the 192.168.2.x network without issue when everything is hooked up.  It can not talk past the m6220 on the 172.16.2.x network WHILE the 192.168.2.x network is active.  If I remove the link to the 192.168.2.x network, data starts flowing from the juniper stack on the 172.16.2.x network.  I hooked wireshark up, and it looks like the juniper stack on the 172.16.2.x network receives arp requests, but doesnt respond while the 192.168.2.x network is connected.  Anymore thoughts?

[nikolay.semov]

Could you please include routing information from all 4 devices? Looking for 192.168.2/23 , 172.16.2/24, and 0/0 routes while your 192.168.2 connection is plugged in and when it's unplugged.

Where did you connect Wireshark?

[jmelcher21]

192.168.2.x ex4200 stack:

0.0.0.0/0              *[static/5] 12w1d17:42:31

                                > to x.x.x.6 via ge-3/0/13.0

                                [OSPF/150] 6w6d 19:31:01

                                Metric 69, tag 1722

                                >to x.x.x.6 via ge-3/0/13.0

192.168.2.0/23   *[direct/0]

                                Local vlan.17

M6220:

C             172.16.2.0/24     [0/1]      directly connected, V110

172.16.2.0 ex4200 stack:

0.0.0.0/0              *[static/5]

                                > to 172.16.2.1 via vlan.10

192.168.2.0/23   *[direct/0]

                                >via vlan.10

That is the routing information before and after removing the link to 192.168.2.x.  Wireshare was plugged in to another port on the 172.16.2.x ex4200 stack that was analyzing both the ingress and egress of the port uplinked to the m6220.  Just to clarify, I'm not interested in routing between these vlans.  Just want the one VM to be dual homed.  The m6620 purposely doesn't have an ip for its vlan17 because it doesn't need to have one, and its management ip is in-band and on the same network, so it won't let me give another interface on that subnet anyways.  I'll remove the ip for vlan10 on the m6220 when I am all done, it only  has one right now so that I can ping.  Only layer 2 stuff is happening.

[nikolay.semov]

Both EX4200 stacks have the same IP subnet configured -- one on VLAN 17, the other on VLAN 10. Typo ??

You did not include routing information from your virtual machine.

With the routing tables as depicted, there's no way for you to ping anything on 192.168.2/23 from the M6220 however things may be connected.

Basically what I'm trying to see is what your connected routes are, and where the default routes go.