MST Root Port Question

[socraticmethod]

This isn't necessarily any issue, I'm just trying to figure out a couple of things about the following log entry.

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Sep 30 15:04:24 STP: MSTI0: New root on port 1, root path cost is 20000


1) Why is MST enabled when the switch is running RSTP?

2) Why is MST selecting root port 1 when there is nothing patched into it?

3) Is this an issue?


See below screenshot and snippet from my Syslog.

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Sep 30 14:53:45 UI: Syslog_Log_Logins: changed from 'Disabled' to 'Enabled'
Sep 30 14:53:48 dropbear[1421]: Premature exit: Terminated by signal
Sep 30 14:53:48 dropbear[547]: Running in background
Sep 30 15:04:12 UI: Configuration changed by admin (10.0.0.77)
Sep 30 15:04:12 UI: Port 11 Name: changed from 'Media Converter' to 'Artist Relations DL'
Sep 30 15:04:22 monitor: restarting vtss_appl
Sep 30 15:04:23 STP: set port 11 to discarding
Sep 30 15:04:23 STP: set port 12 to discarding
Sep 30 15:04:24 STP: set port 11 to learning
Sep 30 15:04:24 STP: set port 11 to forwarding
Sep 30 15:04:24 STP: MSTI0: New root on port 1, root path cost is 20000
Sep 30 15:04:24 STP: set port 12 to learning
Sep 30 15:04:24 STP: set port 12 to forwarding


[Eric Stern]

I'd need to see your STP tab.

[socraticmethod]

Thanks for the response. What is the reason for choosing port 1 as root when there's nothing patched into it?

[Eric Stern]

I tried to duplicate this in my lab but couldn't. Just some kind of fluke I think. Obviously root didn't stay on port 1 as your screenshot shows root on port 12. If you notice it happen again I can look into it more, but I don't think its anything to worry about.

[socraticmethod]

Thanks for the reply. I've seen this log on multiple switches with nothing plugged into Port 1. It doesn't seem to be causing an issue, but I was curious and wanted to see what y'all though. Here's a screen shot from another switch.