3850 - link light on but no cable connected

[jlmickens]

I just completed installation of a stacked pair of 3850s in my datacenter.  While I was installing them, I noticed that the lights on ports 1-8 on one of the switches were on solid even though there were no cables connected to that switch.  I don't see anything in the logs or anywhere else in the CLI that indicate a problem, however the lights remain on.  This only happens on switch 1, not switch 2.  Once I plugged the cable into port 1, it flashes normally with activity, but 2-8 remain on solid even though nothing is connected to them.

Before I put the switches in place, I had configured them at my desk with the console connection, and those lights were not lit up.

The indicators on the front of both switches are set in STAT mode.  I thought initially I had hit the button and flipped it to a different mode, but that is not the case.  Has anyone seen this behavior before?

[glen.grant]

  I think you are one of the lucky few who have equipment that new so you may not get too many answers.

[Bilal Nawaz]

I've seen this on a 3750X just a couple of days ago. But I found that I must have somehow pressed the 'mode' button which caused this. So I started messing around with the mode buttons - was quite a show! But I found that whilst I was doing this, the switch LED's would pause every now and then and stay on... Not sure if this is exactly the same behavior.

just a link here for the LED in case youre interested

http://www.cisco.com/en/US/docs/switches/lan/catalyst3850/hardware/installation/guide/HIGOVERV.html#wp1315536

Please rate useful posts and remember to mark any solved questions as answered. Thank you.

[Chris91130]

I had an issue similar to this one. A user of mine laptop would not connect the network. I noticed her mac on another interface but there wasn't a device connected to that interface. So I went back and unplugged the device from the interface (Interface lights showed activity,) and when i unplugged it, the activity lights were still going. I eventually shut it down and all was well.The device was a 3850.

[jlmickens]

I was a little worried about that Glen.  I may have to open a case...

The lights seem to stay lit regardless of what mode the button switches to.  I think I am going to try a reload of the whole stack.

[jlmickens]

Doing a reload of the stack did the trick.  Luckily the switch was not in production yet, so it wasn't difficult to make that happen.

[Bilal Nawaz]

Rating post so it can help others

Thank you for sharing.

Please rate useful posts and remember to mark any solved questions as answered. Thank you.

[farzu_shaikh]

Even I have same issue.. Any help my aches are inn stack.. Port led on continue.status showing connected with laptop but no Mac learning 

Any help

[justthompson]

I had this issue as well

Reloading the stack fixed the issue.