Problem
After installing a Ubiquiti Unifi US-24-250W switch that had been in storage for a while. I attempted to upgrade the firmware using the controller but kept getting the error.
“upgrade failed firmware check failed”
My switch was on version 4-0-80-10875 and the controller was informing me at the time of writing that the latest version was 5.64.8
What I tried
Pinging the download server
I first confirmed my switch could successfully ping the Unifi download server. I didn’t think there would be a problem here as I had successfully upgraded the firmware on some Unifi AC-Pro and AC-Pro-LR access points on the same site. But it never hurts to check the basics!
- Either SSH onto your switch or use the “Debug Terminal” option. Found by selecting your devices in the Devices section and visiting the tools tab.
- Enter the command ping dl.ubnt.com and you should get successful replies. If not you may have some sort of internet, routing or firewall issue. For me no network issues here
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Caching the firmware
Next I attempted to cache the firmware on the controller in case the switch was having some sort of issue downloading it directly.
- Under Settings => Maintenance I selected the cache option to the right of the firmware release.
- Then attempted another upgrade without success 😢
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Solution – Manual Firmware Upgrade
I’m still not sure why this worked maybe because the version I was upgrading from was a bit too old for the controller to handle. Whatever the reason the below resolved the issue for me.
The next time a firmware update is released I will try and remember to update this post on how the upgrade goes using the normal process. I am hoping this manual firmware upgrade is a one off.
Finding the update URL
When attempting to upgrade the firmware using the controller the “Are you sure” dialogue informed me of the version I needed to find.
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I used the wonder of Google to find the firmware release on the Unifi releases page in my case this was https://community.ui.com/releases/USW-Firmware-5-64-8/c2f999a4-2135-4c9d-a9aa-075acf2c0547
I then right-clicked on the download link for my switch model and copied the link.
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Back on the Unifi controller I used the “Custom upgrade” option for my device.
- Paste in the previous copied URL
- Click “Custom Upgrade”
- Click the “Confirm” button as long as you are sure you have copied the correct firmware link for your device!
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Success! 🥳
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