Hi there,
We're having some intermittent issues with our DC network, which consists of a pair of 2910al-24G with a 2x1Gbe Trunk as a 'Core' layer, and then pairs of 2810-48G switches hanging off of these to form an access layer.
Ideally I'd like to replace the 2910's with a stackable pair to form a core, but it's not on the cards atm...
An network overview diagram looks like:
As marked on the diagram, we've had to increase the Priority values on our Core and Access switches so as not to conflict with our hosting providers upstream Cisco network.
But other than enabling Spanning tree and increasing the priorities, we've done nothing to the default Spanning Tree configuration...
From looking at the Spanning tree stats on the switches, it appears that all the Spanning tree CST Root's are being managed by upstream Cisco switches, which doesnt feel great to me...
As regards network config, we've got 2 VLANs in play, ID's 118 and 119. Any switch-to-switch links are Tagged with the relevant VLAN ID's, as is the Trunk between the 2 core switches.
The core switch spanning-tree config looks like:
SWITCH01# show config ... spanning-tree spanning-tree Trk1 priority 4 spanning-tree priority 9 SWITCH02# show config ... spanning-tree spanning-tree Trk1 priority 4 spanning-tree priority 10
A show spanning-tree on the Core switches gives:
SWITCH01# show spanning-tree
Multiple Spanning Tree (MST) Information
STP Enabled : Yes
Force Version : MSTP-operation
IST Mapped VLANs : 1-4094
Switch MAC Address : 002347-c7b4c0
Switch Priority : 36864
Max Age : 20
Max Hops : 20
Forward Delay : 15
Topology Change Count : 105,253
Time Since Last Change : 6 hours
CST Root MAC Address : 002334-e10c00
CST Root Priority : 0
CST Root Path Cost : 200000
CST Root Port : 23
IST Regional Root MAC Address : 002347-c7b4c0
IST Regional Root Priority : 36864
IST Regional Root Path Cost : 0
IST Remaining Hops : 20
Root Guard Ports :
TCN Guard Ports :
BPDU Protected Ports :
BPDU Filtered Ports :
PVST Protected Ports :
PVST Filtered Ports :
| Prio | Designated Hello
Port Type | Cost rity State | Bridge Time PtP Edge
----- --------- + --------- ----- ---------- + ------------- ----- --- ----
3 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
4 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
5 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
6 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
7 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
8 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
9 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
10 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
11 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
12 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
13 100/1000T | 2000000 128 Forwarding | 002347-c7b4c0 2 Yes No
14 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
15 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes Yes
16 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes Yes
17 100/1000T | Auto 128 Disabled |
18 100/1000T | Auto 128 Disabled |
19 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes Yes
20 100/1000T | Auto 128 Disabled |
21 100/1000T | Auto 128 Disabled |
22 100/1000T | Auto 128 Disabled |
23 100/1000T | 200000 128 Forwarding | 0023ab-dc0880 2 Yes No
24 100/1000T | 200000 128 Blocking | 0023ab-dc0880 2 Yes No
Trk1 | 20000 64 Forwarding | 002347-c7b4c0 2 Yes No
SWITCH02# show spanning-tree
Multiple Spanning Tree (MST) Information
STP Enabled : Yes
Force Version : MSTP-operation
IST Mapped VLANs : 1-4094
Switch MAC Address : 002347-cb1380
Switch Priority : 40960
Max Age : 20
Max Hops : 20
Forward Delay : 15
Topology Change Count : 131,738
Time Since Last Change : 6 hours
CST Root MAC Address : 002334-e10c00
CST Root Priority : 0
CST Root Path Cost : 200000
CST Root Port : 23
IST Regional Root MAC Address : 002347-cb1380
IST Regional Root Priority : 40960
IST Regional Root Path Cost : 0
IST Remaining Hops : 20
Root Guard Ports :
TCN Guard Ports :
BPDU Protected Ports :
BPDU Filtered Ports :
PVST Protected Ports :
PVST Filtered Ports :
| Prio | Designated Hello
Port Type | Cost rity State | Bridge Time PtP Edge
----- --------- + --------- ----- ---------- + ------------- ----- --- ----
3 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
4 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
5 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
6 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
7 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
8 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
9 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
10 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
11 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
12 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
13 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
14 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes No
15 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes Yes
16 100/1000T | 20000 128 Forwarding | 002347-cb1380 2 Yes Yes
17 100/1000T | Auto 128 Disabled |
18 100/1000T | Auto 128 Disabled |
19 100/1000T | Auto 128 Disabled |
20 100/1000T | Auto 128 Disabled |
21 100/1000T | Auto 128 Disabled |
22 100/1000T | Auto 128 Disabled |
23 100/1000T | 200000 128 Forwarding | 0023ab-dc3680 2 Yes No
24 100/1000T | 200000 128 Blocking | 0023ab-dc3680 2 Yes No
Trk1 | 20000 64 Blocking | 002347-c7b4c0 2 Yes No
On one of the access layer switches, it gives:
SWITCH04# show spanning-tree
Multiple Spanning Tree (MST) Information
STP Enabled : Yes
Force Version : MSTP-operation
IST Mapped VLANs : 1,118,119
Switch MAC Address : 002347-101a80
Switch Priority : 61440
Max Age : 20
Max Hops : 20
Forward Delay : 15
Topology Change Count : 333
Time Since Last Change : 19 days
CST Root MAC Address : 002334-e10c00
CST Root Priority : 0
CST Root Path Cost : 220000
CST Root Port : 1
IST Regional Root MAC Address : 002347-101a80
IST Regional Root Priority : 61440
IST Regional Root Path Cost : 0
IST Remaining Hops : 20
Root Guard Ports :
TCN Guard Ports :
Protected Ports :
Filtered Ports :
| Prio | Designated Hello
Port Type | Cost rity State | Bridge Time PtP Edge
----- --------- + --------- ----- ---------- + ------------- ----- --- ----
1 100/1000T | 20000 128 Forwarding | 002347-c7b4c0 2 Yes No
2 100/1000T | 20000 128 Blocking | 002347-cb1380 2 Yes No
3 100/1000T | 20000 128 Forwarding | 002347-101a80 2 Yes Yes
4 100/1000T | 20000 128 Forwarding | 002347-101a80 2 Yes Yes
Any ideas on where I should start with trying to get this all setup correctly?
Cheers
Gavin
P.S. This thread has been moved from Switches, Hubs, Modems (Legacy ITRC forum) to ProCurve / ProVision-Based. - Hp Forum Moderator
A pair of 3800 for the core would be nice, maybe you can work on that for the next budget cycle!
The high topology change count on all the switches seems to indicate something is not right, with some sort of STP flapping going on.
What are you going to do about the Cisco switches? Are they in or out of scope? You will need to work out where your root STP switch need to be, and work from there. If you put aside the Cisco switches for the moment, switch01 may as well be the STP root.
Make sure switch01 is priority 0, switch02 is priority 1 (alt root), and the remaining 2810s leave at priority 15. there are other STP protection mechanisms that may be relevant with the Ciscos (they are probably using RSTP/RSTP+).
You need to work out how to include the hosting provider Cisco switches though; you may need to call them and discuss the issue.
FYI, you can download and use the 60-day eval version of HP IMC to show a GUI of exactly what is going on with STP.
