4510 Switchport Access

[zekebashi]

Hello, 

I have a 4510E iand a 3750 with 4 stacked switches in a lab environment . On the 4510, I have g1/48 configured as switch mode access port and  switch access vlan 182. On the 3750, I have port Fa1/17 configured the same way. I rebooted the 4510 and then port g1/48 was disabled and port fa1/17 went into errdisable mode. The strange thing is that before I rebooted the 4510, the uplink between the two switches was working just fine.  I have recently update the IOS on the 4510 and that was before I rebooted it. 

Any thoughts as to why this issue is happening?? Why do the ports go into errdisable when they are uplinked while configured as switchport access? 

Thanks in advance. 

Best, ~zK

[Leo Laohoo]

Port went into error-disabled possibly caused by BPDU Guard enabled globally?

[Joseph W. Doherty]

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Posting

Like Leo, my first guess would be BPDU Guard.  Do you have an internal syslog configured?  If so, did you check it for any messages about the port?

[zekebashi]

Correct. The BPDU Guard is enabled; however, a former eng. setup the ports that way and I was planning on changing those 2 ports to Trunk ports rather than access ports. Changing the ports to trunk ports is pretty straight forward!

The one thing that I would like to get clarification on is, if configuring the ports as L3 ports, do I need to configure them as access ports? The answer to me should be "NO" but I want to make sure that my understanding was correct. 

Thanks so much for your assistance!!! 

Best, ~zK 

[Robert Falconer · Accepted solution]

If you want to configure them as L3 ports, then they won't be access ports. Access ports are L2.

You'll probably need to issue the command 'no switchport' on the interfaces before assigning an IP address to them.

[zekebashi]

Thank you for the prompt answer! 

Much appreciated. 

~zK