HP ProCurve Spanning Tree

We have two core procurve switches (5304xl), and a server that does NIC Teaming.

NIC Team:
Server NIC1 - connects to switch 1 (port C10)
Server NIC2 - connects to switch 2 (port A4)

The two switches are connected via a 4-port trunk, and have spanning tree enabled.

I'm assuming that since the switches are not aware of any "link aggregation" going on, they are using Spanning Tree to block one of these ports.

How do I find out on the switch side if either port C10 on switch1 is being blocked by spanning tree, or if the other port on switch 2 is being blocked?
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pzozulkaAsked:
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jburgaardCommented:
If spanning tree was in a blocking state somewhere on a switch
show span
would show.
In the log a message would show up, when state is changed.

AFAIK you can not split a NIC-team between the 2 5304xl.
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pzozulkaAuthor Commented:
Here are the results of "show span". I cannot tell whether spanning tree is or is NOT blocking a port.

                  |           Prio             | Designated    Hello
  Port  Type      | Cost      rity  State      | Bridge        Time  PtP Edge
  ----- --------- + --------- ----- ---------- + ------------- ----- --- ----
  A1    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  A2    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  A3    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  A4    100/1000T | Auto      128   Disabled   |
  A7    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  A8    100/1000T | Auto      128   Disabled   |
  A9    100/1000T | Auto      128   Disabled   |
  A10   100/1000T | Auto      128   Disabled   |
  A11   100/1000T | Auto      128   Disabled   |
  A12   100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  A13   100/1000T | Auto      128   Disabled   |
  A15   100/1000T | Auto      128   Disabled   |
  A16   100/1000T | Auto      128   Disabled   |
 B1    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  B2    100/1000T | Auto      128   Disabled   |
  B3    100/1000T | Auto      128   Disabled   |
  B4    100/1000T | Auto      128   Disabled   |
  B5    100/1000T | Auto      128   Disabled   |
  B6    100/1000T | Auto      128   Disabled   |
  B7    100/1000T | Auto      128   Disabled   |
  B8    100/1000T | Auto      128   Disabled   |
  B9    100/1000T | Auto      128   Disabled   |
  B10   100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  B11   100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  B12   100/1000T | Auto      128   Disabled   |
  B13   100/1000T | Auto      128   Disabled   |
  B15   100/1000T | Auto      128   Disabled   |
  B16   100/1000T | Auto      128   Disabled   |
  C1    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C2    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C3    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C4    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C5    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C6    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C7    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C8    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  C9    100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  C10   100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  C11   100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes Yes
  C15   100/1000T | 20000     128   Forwarding | 001321-128b00 2     Yes No
  Trk1            | 20000     64    Forwarding | 001321-128b00 2     Yes No
  Trk5            | 20000     64    Forwarding | 001321-128b00 2     Yes Yes
  Trk6            | 20000     64    Forwarding | 001321-128b00 2     Yes Yes

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Also, the image below is showing our NIC-team config. Although these NIC-Teams are not able to take advantage of bandwidth improvements, they are able to take advantage or redundant switches. In case one switch goes down, the other will continue to server traffic with zero environment down time.NIC Teams
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jburgaardCommented:
If spanning tree was blocking, the 'state' would tell, so here are no blocked ports or trunks shown.
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pzozulkaAuthor Commented:
What's the difference between "forwarding" and "disabled"?
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jburgaardCommented:
"forwarding" means ready
"disabled" could be port down or administratively disabled by you
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jburgaardCommented:
show int brief
will show port status as up, down
a port can be up -but in a blocking state, ready to change state, when the topology changes
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pzozulkaAuthor Commented:
Hmmm...this still doesn't answer my question on how to check if spanning tree is blocking one of the two ports.
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jburgaardCommented:
If you check BOTH the 2 switches and you find that no ports are in blocking state at that point in time, then stp is not blocking trafic at that time.

Old STP-events can be found in logs on the sw's.

You can see stats for a port like c10:
show int c10

Real-time trafic can be looked at by means of the web-interfaces to the switches.
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pzozulkaAuthor Commented:
OK, so it appears that "show span" does not show any "Blocked" ports on either switch. All of them either say Disabled or Forwarding.

However, the logs seem to show something a bit different. The below ports are part of the NIC team.

Switch 1:
I 09/23/13 16:03:55 ports: port B10 is now off-line
I 09/23/13 16:04:03 ports: port B10 is Blocked by LACP
I 09/23/13 16:04:06 ports: port B10 is Blocked by STP
I 09/23/13 16:04:09 ports: port B10 is now on-line
I 09/23/13 16:05:12 ports: port B10 is now off-line
I 09/23/13 16:05:15 ports: port B10 is Blocked by LACP
I 09/23/13 16:05:18 ports: port B10 is Blocked by STP
I 09/23/13 16:05:20 ports: port B10 is now on-line
I 09/23/13 16:06:37 ports: port B10 is now off-line
I 09/23/13 16:06:40 ports: port B10 is Blocked by LACP
I 09/23/13 16:06:43 ports: port B10 is Blocked by STP
I 09/23/13 16:06:46 ports: port B10 is now on-line
I 09/23/13 16:06:53 ports: port B10 is now off-line
I 09/23/13 16:06:56 ports: port B10 is Blocked by LACP
I 09/23/13 16:06:59 ports: port B10 is Blocked by STP
I 09/23/13 16:07:02 ports: port B10 is now on-line

Eventually port B10 is on-line...

Switch 2:
I 09/23/13 17:03:52 ports: port A6 is now off-line
I 09/23/13 17:03:54 ports: port A6 is Blocked by LACP
I 09/23/13 17:03:57 ports: port A6 is now off-line
I 09/23/13 17:04:00 ports: port A6 is Blocked by LACP
I 09/23/13 17:04:00 ports: port A6 is Blocked by STP
I 09/23/13 17:04:03 ports: port A6 is now on-line
I 09/23/13 17:06:32 ports: port A6 is now off-line
I 09/23/13 17:06:35 ports: port A6 is Blocked by LACP
I 09/23/13 17:06:38 ports: port A6 is Blocked by STP
I 09/23/13 17:06:41 ports: port A6 is now on-line

Eventually port A6 is on-line...

What do these logs tell you?
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jburgaardCommented:
when a port is on its way up and working it will transit some states 'Blocked by LACP' ,
'Blocked by STP' and 'now on-line'
that is normal with these protocols working.
What could be anormal is the repeated short time between the on-line to off-line states.
So I would focus on the vm-NIC's
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pzozulkaAuthor Commented:
Are you saying that there is no "loop" on the network NOT because spanning tree is blocking something, but perhaps because the vm-NICs are "blocking" on their end?
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jburgaardCommented:
I will not jump to conclusions on the vm-side.

In a stable network with phy-switches a potential loop and STP blocking somewhere to prevent this loop, there would not be this high freqency of flapping:
-On a 'spanning tree accessport' (portfast) link there would be a repeated pattern of short broadcast-storm - then blocking for perhaps a few minutes.
-On a 'no spanning tree accessport' (that is a link between switches) the port would be in a stable blocking state.
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pzozulkaAuthor Commented:
Hmm...then not sure where else to look to determine how this NIC Team is working the way it is.

I mean everything is working fine -- and I don't think there are any problems with this NIC Team connecting to different switches. Afterall, I would think this would be a recommended strategy so that if one switch fails traffic would continue flowing uninterupted. In fact we tested this and it worked fine.

The reason I'm trying to get to the bottom of this is I NEED to understand how this is working. Either STP is blocking one the ports which would explain a lot. Or my only ohter conslusion would be the NIC team is isolating one of the NICs -- even though they are both setup as Active NICs.

Where else do I look to get to the bottom of this. Tried the logs and tried "show span".
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jburgaardCommented:
I am not an expert on vm's and cannot tell where to look inside these.
But as far as I hear the STP is not blocking anything on the outside.
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