Loss of connectivity from switch

[Cory King]

Hi all, 

I have a couple of strange issues that I'm hoping you can help with or point me in the right direction.  We have a couple of locations that have been seeing switch type lockups.  What I mean by that is the switch stops passing traffic, but not all.  For example, today there was an alert from an office that they were down, yet I was able to reach the core switch and ping outbound and over the dmvpn network.  However if I ran a show lldp neigh or show cdp nei, there was only a couple of entries when the whole switch has phones on it so there should have been about 30 at least show up.  The router didn't even appear yet I could ping through it.  To add more context this site, and most our sites, is pretty straightforward meaning INTERNET >> Cisco Router >> 2960X (core) << 2960X (edge).  When we rebooted the switch, everything came back as it should.  The logs on the switch just showed that things started dropping off and authentication issues (we have ISE also).  It almost seemed like processes/services just stopped working on the switch.  Switches are at 15.2(7)E4.

Any insight would be appreciated.  Thanks!

[Kasun Bandara · Accepted solution]

its very strange situation. i think you should open TAC and check for any unknown bugs