3650 - AT&T ASE circuit - IOS upgrade breaks connection

[sbrock]

I'm running IOS 03.03.03SE on a 3650-48PD switch.  I have an AT&T ASE circuit that connects to our other locations.  The port uses a 1000BaseSX SFP module and is configured as:

interface GigabitEthernet2/1/1

no switchport
 ip address 10.254.1.XX 255.255.255.0
 spanning-tree portfast

This setup works.  I can see my other locations if I sh cdp neighbors and all the IP routes with sh ip route.  However, if I upgrade the IOS, the connection breaks.  The connections leds on the port do not turn green.  Doing a show int gi2/1/1, it show the interface is down and the line protocol is down.  Only local IP routes are seen.

I've tried different versions of IOS.  Today, I tried 03.07.05.  I've tried 03.06.05 in the past.  Is there any other setup that I may be missing?  Should I set the speed and duplex manually?  After performing a software update and the setup doesn't work, I've used the "software rollback" function to revert back to 03.03.03.  Once the switch is back on the 03.03.03 version, the port config works and I see traffic passing across the port.

Thanks,

Scott

[Mark Malone · Accepted solution]

hi

3.6.6 I the current recommended image for that platform and is stable  , yes try turn off the negotiation after the upgrade by hard setting the speed/duplex  speed 1000 , duplex full or whatever its autos to and works on 3.3

[sbrock]

At a different location, I upgraded a 3650 from 3.05.05 to 3.6.6.  This switch had this configuration:

 no switchport
 ip address 10.254.1.XX 255.255.255.0
 speed nonegotiate
 priority-queue out
 spanning-tree portfast

This configuration works.  Based on this, I'll add the "speed nonegotiate" command to the switch running 3.3.3 and upgrade to 3.6.6.