How to fix a bad iCloud Backup from hogging your network bandwidth
It baffled me for the longest time, at first I thought it was me being crazy but eventually I realized whenever my iPhone was plugged in (regardless if it was my MBP, my PS4, or a wall outlet) the internet would start to get very slow on all my other devices and often kill it all together. This is how I stopped my iCloud backup from hogging my internet bandwidth.
Finding the Issue
At first I thought it was iCloud photos so I turned off iCloud photos but I still had the issue. Then I noticed when my internet was slow, iCloud backup was running on my iphone. I downloaded the WifiMan app to check how much data was being used and it was hogging A LOT of my bandwidth. I tried to let the back up finish but it never did.
iCloud back up was the issue but why? Later when I’d connect my iPhone to my MacBook there were 5 photos that would never import. Going through my phone and noticed several copies of the same photos. Here’s the problem!
How I Fixed it
To fix the , back up all photos and try to backup your iPhone via iTunes. Next, I recommend a factory reset of your phone and to set your iPhone up as a new iphone. I did this as a precaution and I didn’t want to deal with another corrupt backup. After setting up the iPhone, run a new backup and this should work correctly.
A corrupt iCloud backup is a pain, and even figuring out why your iPhone being connected via USB causes your internet to crash is even harder. This took me longer than it should have to realize but I’m happy that it’s resolved now. As a side note, my ISP just started charging for data caps so I check my data usage and sure enough I went WAY over what I expected for the month. Glad I caught this issue in time before my ISP started charging me for the zombie iCloud backup.