This is something that happened as I was setting up a couple of these PoE SF300 switches for IP cameras.
We wanted to save a little money so we purchased a few of these switches to daisy-chain onto a couple of our 4507s to provide PoE support for IP cameras that are coming in. But an odd thing happened when I set one up and connected it.
I set up the SF300 switch with all FE ports set to access and for VLAN 18 (our camera VLAN). I then configured a Portchannel (PO2) and assigned GE1 and GE2 to it. I defined the allowed VLANs 10,14,18 on the Port Channel Interface definition. I also created an SVI Interface VLAN definition for our management address (on VLAN 10) to be able to SSH into the switch once it's on the network.
I did most of this thru the CLI and not the GUI.
I saved the config (copy run start) and turned off the switch then deployed it in the IDF closet. I powered it up and connected the GE1&2 ports to 2 Gig ports in the 4507 defined with PO2 - both with MODE=ON.
Well, as I found out later, my config changes never got saved and the GE1&2 because trunk ports, so when I plugged them in, They started acting independently. At about the same time another switch we have in our network (that is daisy-chained off a 3750 - 1 trunk port) suddenly had it's uplink put into ERR_DISABLE mode (we also had this occur with another 2 switches with a very similar config - Daisy-Chain).
Now , how my config never got saved issue, is not at the forefront of my mind as much as how did a couple of switch uplinks in another building go into ERR-DISABLE.
I know that our 4507s run rapid per-vlan STP+ and that the SP300 only runs Rapid STP, but this is a real mystery to us. If anyone has any ideas for tracking this down, please reply.