Cisco IOS switch: what spanning tree changes have occurred in the last 24 hours?

I have been troubleshooting an issue of some voip problems at a site. A colleague who's now left mentioned he had run into some spanning tree issues that had caused problems. He fixed that problem he said by adding "portfast" to the access switches. I'm seeing most of these ports set to port type "access" and BPDU guard is set. But I want to verify that changes in spanning tree are not happening which might affect traffic. Are there command that would let me see recent spanning tree change events? Or would I only be able to see this with debug?
LVL 2
amigan_99Network EngineerAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

JustInCaseCommented:
Generally, you can check number of STP changes and last convergence time with command
show spanning-tree
Also, you can get shorter output by REGEX (can be IOS dependent)
sh spanning-tree | i last_change|VLAN|topology_ch

Also check logs:
sh logg

#sh spanning-tree

 VLAN10 is executing the ieee compatible Spanning Tree protocol
  Bridge Identifier has priority 32768, address 649e.f3d4.01fc
  Configured hello time 2, max age 20, forward delay 15
  We are the root of the spanning tree
  Topology change flag not set, detected flag not set
  Number of topology changes 0 last change occurred 18:14:26 ago
  Times:  hold 1, topology change 35, notification 2
          hello 2, max age 20, forward delay 15
  Timers: hello 1, topology change 0, notification 0, aging 300

sh spanning-tree | i last_change|VLAN|topology_ch
 VLAN10 is executing the ieee compatible Spanning Tree protocol
  Number of topology changes 0 last change occurred 18:18:06 ago
  Times:  hold 1, topology change 35, notification 2
  Timers: hello 1, topology change 0, notification 0, aging 300
 Port 7 (FastEthernet6) of VLAN10 is forwarding
 Port 8 (FastEthernet7) of VLAN10 is forwarding

Open in new window

1

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Networking Protocols

From novice to tech pro — start learning today.