Hash Sum Mismatch on apt update

[Cecil]

Got this error last night upon running sudo apt update, and it's still persisting this morning. The error happens on official ubuntu repositories. Here's a copy-paste of the terminal output;

Get:1 http://us.archive.ubuntu.com/ubuntu xenial InRelease [116 kB]
Hit:2 http://archive.canonical.com/ubuntu xenial InRelease                  
Hit:3 http://ppa.launchpad.net/claydoh/kmymoney2-kde4/ubuntu xenial InRelease
Get:4 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu xenial InRelease [23.0 kB]
Hit:5 http://us.archive.ubuntu.com/ubuntu xenial-updates InRelease          
Hit:6 http://us.archive.ubuntu.com/ubuntu xenial-backports InRelease        
Hit:7 http://us.archive.ubuntu.com/ubuntu xenial-security InRelease      
Get:8 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages [1,433 kB]
Hit:9 http://ppa.launchpad.net/libretro/testing/ubuntu xenial InRelease     
Hit:10 http://ppa.launchpad.net/mkusb/ppa/ubuntu xenial InRelease           
Hit:11 http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu xenial InRelease     
Get:12 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu xenial/main amd64 Packages [10.5 kB]
Get:13 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu xenial/main i386 Packages [10.5 kB]
Ign:14 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu xenial/main Translation-en
Get:14 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu xenial/main Translation-en [4,723 B]
Err:8 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages        
  Hash Sum mismatch
Get:15 http://us.archive.ubuntu.com/ubuntu xenial/main i386 Packages [1,428 kB]
Err:15 http://us.archive.ubuntu.com/ubuntu xenial/main i386 Packages
  Hash Sum mismatch
Get:16 http://us.archive.ubuntu.com/ubuntu xenial/main Translation-en [732 kB]
Get:17 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 DEP-11 Metadata [624 kB]
Get:18 http://us.archive.ubuntu.com/ubuntu xenial/main DEP-11 64x64 Icons [410 kB]
Get:19 http://us.archive.ubuntu.com/ubuntu xenial/universe amd64 Packages [7,247 kB]
Err:19 http://us.archive.ubuntu.com/ubuntu xenial/universe amd64 Packages   
  Hash Sum mismatch
Get:20 http://us.archive.ubuntu.com/ubuntu xenial/universe i386 Packages [7,228 kB]
Err:20 http://us.archive.ubuntu.com/ubuntu xenial/universe i386 Packages    
  Hash Sum mismatch
Get:21 http://us.archive.ubuntu.com/ubuntu xenial/universe Translation-en [4,188 kB]
Get:22 http://us.archive.ubuntu.com/ubuntu xenial/universe amd64 DEP-11 Metadata [1,813 kB]
Get:23 http://us.archive.ubuntu.com/ubuntu xenial/universe DEP-11 64x64 Icons [7,462 kB]
Fetched 32.7 MB in 47s (690 kB/s)                                           
Reading package lists... Done
E: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/xenial/main/binary-amd64/Packages.xz  Hash Sum mismatch
E: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/xenial/main/binary-i386/Packages.xz  Hash Sum mismatch
E: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/xenial/universe/binary-amd64/Packages.xz  Hash Sum mismatch
E: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/xenial/universe/binary-i386/Packages.xz  Hash Sum mismatch
E: Some index files failed to download. They have been ignored, or old ones used instead.

Edit: Running apt update a couple more times, and the issue's cleared up. Are the hashes for the package lists simply being updated late or something, so it causes a mismatch when I download them? Or is something happening to the download between the server and my computer?

[Snowhog]

It could be a timing issue (maybe) in that the repository(ies) might not have been completely finished updating, or corruption in the data transmission. Just guesses.

I will either stop the update and redo it, or sometimes, change the server. What I don't do is continue with a dist-upgrade when the update shows Hash Sum mismatches.

[eddieg538]

Same thing happened to me. I tried 2 hours later and all went fine.

[jlittle]

Similar happened to me, repeating a few times, on different items each time. I switched servers^* to the "Main Server" and it went away.
I would have just waited but I'm setting up a new machine and installing lots, so switching servers let me get on with it.

^* On the K menu, System, Update Manager, More..., Advanced > Configure Software Sources.

[Cecil]

Similar happened to me, repeating a few times, on different items each time. I switched servers^* to the "Main Server" and it went away.
I would have just waited but I'm setting up a new machine and installing lots, so switching servers let me get on with it.

^* On the K menu, System, Update Manager, More..., Advanced > Configure Software Sources.

Yeah, I decided to switch to the Main Server, after realizing that was the server earlier versions of Kubuntu defaulted to. Hopefully no more mismatches. Also, yeah, I definitely wasn't going to do an upgrade while the repositories were complaining of a hash mismatch.