troubleshooting Question

spanning-tree issue

Avatar of Shark Attack
Shark Attack asked on
Switches / HubsNetworking
4 Comments2 Solutions113 ViewsLast Modified:
I dont know why I'm having this issue but it's happenig. I am working on basic topology. Router to layer 3 switch to little trendnet L2 switch to hosts. Image attached. Very simple. For some reason, the switch in the middle, STP is blocking the port. I have no idea why. How can I fix this and why it this even blocked, there is no redundant links
interface GigabitEthernet0/4
 switchport access vlan 100
 switchport mode access
 switchport nonegotiate
 switchport port-security maximum 4
 switchport port-security violation restrict
 switchport port-security aging time 60
 switchport port-security aging type inactivity
 switchport port-security
 no keepalive

TEST_SW#sh spanning-tree blockedports

Name                 Blocked Interfaces List
-------------------- ------------------------------------
VLAN0100             Gi0/4

Number of blocked ports (segments) in the system : 1

There is no even loop. It's one link to the L2 switch thats all.

Can anyone help that actually know whats going on here? Lately I've been getting a lot of answers that were useless to me and did not help. Thank you
Shark AttackNetwork admin

Our community of experts have been thoroughly vetted for their expertise and industry experience.

Join our community to see this answer!
Unlock 2 Answers and 4 Comments.
Start Free Trial
Learn from the best

Network and collaborate with thousands of CTOs, CISOs, and IT Pros rooting for you and your success.

Andrew Hancock - VMware vExpert
See if this solution works for you by signing up for a 7 day free trial.
Unlock 2 Answers and 4 Comments.
Try for 7 days

”The time we save is the biggest benefit of E-E to our team. What could take multiple guys 2 hours or more each to find is accessed in around 15 minutes on Experts Exchange.

-Mike Kapnisakis, Warner Bros