Just a note letting you know, after updating 9 AP's from 3.22 (411a's and 433's) to 4.2 and upgrading the license as needed I have run into severe problems. 4.2 drops ethernet ports randomly and there seems to be no set pattern as well. This is a very serious problem. Our AP's are scattered over 2,000 square miles. This is not a cable or power problem. Most of these AP's have been running over 6 months without a reboot. Until 4.2. Power cycle brings everything back up. It was approximately 36 hours after the upgrade when they started dropping ethernet ports.

more info.

dropped means the interface disappeared? dropped packets? stopped and then started?

Please, anyone having these interface issues, take a supout before AND after you reboot and send it to support. It's going to take longer to get it fixed if you just report it here but take no action with support.

I'm sorry about the support file. I was frantic trying to get everything back up online. In each case I could not get to the AP, because the back haul is connected to the AP by ethernet. So getting that file was not possible. Also, on at least two of them it dropped access to the radio as well, very possibly all of them. But there was no way for me to check that on two of them because I live to far away just to run and see if I can see a radio or not. My clients don't have Winbox access to anything.
When checking the ethernet port from the BH Routerboard to the AP Routerboard I showed connectivity, but no traffic was going through. I could not ping the AP from either side, nor could I telnet or mac address into it. Kind of like the whole thing was locked up.
My whole network is one big bridge. All BH's and AP's are bridged. Yes, it seems like a silly way of doing things, but in a year and half, we have never had any issues.
If you have more questions please let me know. Right now I need to downgrade everything back to 3.22 or 3.30. What do you recommend? 3.22 was great, though now 3.30 is a stable release.

Thanks

I'm bench testing downgrading everything now. The 411 that I updated to 4.2 on my bench went fine. Then I wanted to downgrade it to make sure it keeps its complete configuration.
a. It had the license key on the board that it makes when you upgrade 3.xx to 4.xx. I saved that locally as well.
b. Copied 3.22 (only dhcp, routerboard, wireless, system, because that is all I use) to 411.
c. Selected the four packages for 4.2 and selected downgrade. That was a mistake

When the board came back online it wants a license key. The one I have for it will not work. I guess you are suposed to downgrade the license before downgrading the firmware. Who do I contact now to get a license to fix that board. Hopefully I don't have to buy another license.