Failed to fetch url Hash Sum mismatch Ubuntu 18.04 LTS

I have tested all answers of this link. Unfortunately, none of them solved my problem.

When I fire apt update up, it gives me:

Hit:1 bionic InRelease
Get:2 bionic-security InRelease [88.7 kB]
Get:3 bionic-updates InRelease [88.7 kB]
Get:4 bionic-proposed InRelease [242 kB]
Hit:5 bionic-backports InRelease
Get:6 bionic/multiverse Sources [181 kB]
Get:7 bionic/restricted Sources [5,324 B]
Get:8 bionic/universe Sources [9,051 kB]
Get:9 bionic/main Sources [829 kB]
Get:10 bionic-security/restricted Sources [4,548 B]
Get:11 bionic-security/universe Sources [167 kB]
Get:12 bionic-security/multiverse Sources [3,180 B]
Get:13 bionic-security/main Sources [143 kB]
Get:14 bionic-security/main i386 Packages [442 kB]
Get:15 bionic-security/main amd64 Packages [651 kB]
Get:16 bionic-security/main Translation-en [211 kB]
Get:17 bionic-security/main amd64 DEP-11 Metadata [38.5 kB]
Get:18 bionic-security/main DEP-11 48x48 Icons [17.6 kB]
Get:19 bionic-security/main DEP-11 64x64 Icons [41.5 kB]
Get:20 bionic-security/restricted amd64 Packages [23.8 kB]
Get:21 bionic-security/restricted i386 Packages [4,280 B]
Get:22 bionic-security/restricted Translation-en [6,528 B]
Get:23 bionic-security/universe i386 Packages [617 kB]
Get:24 bionic-security/universe amd64 Packages [649 kB]
Get:25 bionic-security/universe Translation-en [218 kB]
Get:26 bionic-security/universe amd64 DEP-11 Metadata [42.1 kB]
Get:27 bionic-security/universe DEP-11 48x48 Icons [16.4 kB]
Get:28 bionic-security/universe DEP-11 64x64 Icons [111 kB]
Get:29 bionic-security/multiverse i386 Packages [4,292 B]
Get:30 bionic-security/multiverse amd64 Packages [6,760 B]
Get:31 bionic-security/multiverse Translation-en [2,700 B]
Get:32 bionic-security/multiverse amd64 DEP-11 Metadata [2,464 B]
Get:32 bionic-security/multiverse amd64 DEP-11 Metadata [2,464 B]
Get:34 bionic-security/multiverse DEP-11 48x48 Icons [29 B]
Get:35 bionic-security/multiverse DEP-11 64x64 Icons [2,638 B]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:36 bionic-updates/main Sources [311 kB]
Get:45 bionic-updates/multiverse Sources [5,840 B]
Get:46 bionic-updates/restricted Sources [6,536 B]
Get:47 bionic-updates/universe Sources [278 kB]
Get:48 bionic-updates/main i386 Packages [651 kB]
Err:48 bionic-updates/main i386 Packages Hash Sum mismatch Hashes of expected file: - Filesize:650672 [weak] - SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx - SHA1:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] - MD5Sum:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] Hashes of received file: - SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx - SHA1:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] - MD5Sum:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] - Filesize:650672 [weak] Last modification reported: Sat, 07 Mar 2020 12:57:17 +0000 Release file created at: Sat, 07 Mar 2020 14:34:50 +0000
Get:49 bionic-updates/main amd64 Packages [871 kB]
Err:49 bionic-updates/main amd64 Packages
Get:50 bionic-updates/universe Translation-en [326 kB]
Get:51 bionic-updates/universe amd64 DEP-11 Metadata [264 kB]
Get:52 bionic-updates/universe DEP-11 48x48 Icons [193 kB]
Get:53 bionic-updates/universe DEP-11 64x64 Icons [438 kB]
Get:54 bionic-updates/multiverse amd64 Packages [10.1 kB]
Get:55 bionic-updates/multiverse i386 Packages [7,476 B]
Get:56 bionic-updates/multiverse Translation-en [4,636 B]
Get:57 bionic-updates/multiverse amd64 DEP-11 Metadata [2,468 B]
Get:58 bionic-updates/multiverse DEP-11 48x48 Icons [29 B]
Get:59 bionic-proposed/multiverse Sources [1,796 B]
Get:60 bionic-proposed/universe Sources [20.5 kB]
Get:61 bionic-proposed/main Sources [66.6 kB]
Get:62 bionic-proposed/restricted Sources [5,592 B]
Get:63 bionic-proposed/main amd64 Packages [111 kB]
Get:64 bionic-proposed/main i386 Packages [82.0 kB]
Get:65 bionic-proposed/main Translation-en [39.0 kB]
Get:66 bionic-proposed/main amd64 DEP-11 Metadata [3,580 B]
Get:67 bionic-proposed/main DEP-11 48x48 Icons [29 B]
Get:68 bionic-proposed/main DEP-11 64x64 Icons [5,301 B]
Get:69 bionic-proposed/restricted i386 Packages [7,820 B]
Get:70 bionic-proposed/restricted amd64 Packages [16.8 kB]
Get:71 bionic-proposed/restricted Translation-en [5,732 B]
Get:72 bionic-proposed/universe amd64 Packages [141 kB]
Get:73 bionic-proposed/universe i386 Packages [134 kB]
Get:74 bionic-proposed/universe Translation-en [27.6 kB]
Get:75 bionic-proposed/universe amd64 DEP-11 Metadata [13.1 kB]
Get:76 bionic-proposed/universe DEP-11 48x48 Icons [5,921 B]
Get:77 bionic-proposed/universe DEP-11 64x64 Icons [16.2 kB]
Get:78 bionic-proposed/multiverse i386 Packages [3,264 B]
Get:79 bionic-proposed/multiverse amd64 Packages [7,588 B]
Get:80 bionic-proposed/multiverse Translation-en [2,836 B]
Get:81 bionic-proposed/multiverse amd64 DEP-11 Metadata [2,468 B]
Get:82 bionic-proposed/multiverse DEP-11 48x48 Icons [29 B]
Get:83 bionic-proposed/multiverse DEP-11 64x64 Icons [2,638 B]
Get:84 bionic-backports/main Sources [2,532 B]
Get:85 bionic-backports/universe Sources [2,496 B]
Fetched 18.0 MB in 1min 11s (253 kB/s)
Reading package lists... Done
E: Failed to fetch Hash Sum mismatch Hashes of expected file: - Filesize:650672 [weak] - SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx - SHA1:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] - MD5Sum:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] Hashes of received file: - SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx - SHA1:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] - MD5Sum:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx [weak] - Filesize:650672 [weak] Last modification reported: Sat, 07 Mar 2020 12:57:17 +0000 Release file created at: Sat, 07 Mar 2020 14:34:50 +0000
E: Failed to fetch
E: Some index files failed to download. They have been ignored, or old ones used instead.

The /etc/apt/sources.list:

###### Ubuntu Main Repos
deb bionic main restricted universe multiverse
deb-src bionic main restricted universe multiverse
###### Ubuntu Update Repos
deb bionic-security main restricted universe multiverse
deb bionic-updates main restricted universe multiverse
deb bionic-proposed main restricted universe multiverse
deb bionic-backports main restricted universe multiverse
deb-src bionic-security main restricted universe multiverse
deb-src bionic-updates main restricted universe multiverse
deb-src bionic-proposed main restricted universe multiverse
deb-src bionic-backports main restricted universe multiverse 

I don't know why exactly it is happening and what's the solution.

Thanks in advance.

2 Answers

This was reported as a bug here and the solution that helped me was this

or follow these steps:

1. sudo rm -rf /var/lib/apt/lists/*
2. sudo apt-get update -o Acquire::CompressionTypes::Order::=gz
3. sudo apt-get update && sudo apt-get upgrade

Hope it works for anyone with the same issue.

Every repository holds a Release file that clients will look for when preforming apt commands. The Release file holds information about the available dists and components (such as bionic main universe and etc.). It specifies the locations and hash sums of every component. Once getting the relevant dist, the client then searches for a package list, containing every available debian, its location, its full name, version, hash sums, size and more. That is how you can differ packages from one repo to another.

If this is an official repository and not a local one managed by you or your organization, there isn't much you can do regarding this specific repo. The administrators must correct this problem, as it is a server side problem.

If you need need a package or an update and don't want to wait - you might want to change or add repositories of other regions by running relevant apt commands: add-apt-repository deb distro component

You can also edit the source list manually at /etc/apt/sources.list with the repos you seek, by adding repo paths: deb distro component

Also: if you're using a desktop OS, you can also use the software center.