Creating mirror list by ranking always breaks system updating

Good morning,

as far as I can remember, ranking mirrors has always broken the ability to update my system. Today, it happened again, and I wanted to try and document what I did in the hopes of finding out how to prevent this in the future.

Today, Discord didn’t want to start and showed an update notification. I know that, so I did a system update using yay -Syu:

[dromundkaas@Pure Videos]$ yay -Syu
[sudo] Passwort für dromundkaas: 
:: Paketdatenbanken werden synchronisiert …
 endeavouros                                                                                                        26,7 KiB   140 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 core                                                                                                              127,6 KiB   539 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 extra                                                                                                               8,3 MiB  3,94 MiB/s 00:02 [----------------------------------------------------------------------------------------] 100%
 multilib                                                                                                          141,5 KiB   615 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
:: Durchsuche AUR nach Updates...
:: Durchsuche Datenbanken nach Updates...
 -> Als nicht aktuell markierte AUR-Pakete: protontricks
:: 14 packages to upgrade/install.
14  endeavouros/endeavouros-mirrorlist  23.10-1    -> 23.12-1
13  endeavouros/eos-bash-shared         23.8-1     -> 23.9-1
12  endeavouros/eos-rankmirrors         2.19-1     -> 2.20-1
11  endeavouros/eos-translations        23.7-1     -> 23.9-1
10  core/archlinux-keyring              20230821-2 -> 20230918-1
 9  extra/discord                       0.0.29-1   -> 0.0.30-1
 8  extra/imagemagick                   7.1.1.15-4 -> 7.1.1.16-1
 7  extra/libdeflate                    1.18-1     -> 1.19-1
 6  extra/mutter                        44.4-1     -> 44.5-1
 5  extra/python-pillow                 10.0.0-2   -> 10.0.1-1
 4  extra/python-typing_extensions      4.7.1-1    -> 4.8.0-1
 3  extra/unrar                         1:6.2.10-1 -> 1:6.2.11-1
 2  extra/vte-common                    0.72.2-2   -> 0.74.0-1
 1  extra/vte3                          0.72.2-2   -> 0.74.0-1
==> Pakete zum Ausschließen: (z.B. "1 2 3", "1-3", "^4" oder Repo-Name)
 -> Das Ausschließen von Paketen kann zu teilweisen Aktualisierungen führen und Systeme beschädigen.
==> 
Sync Explicit (4): eos-rankmirrors-2.20-1, unrar-1:6.2.11-1, endeavouros-mirrorlist-23.12-1, discord-0.0.30-1
Sync Dependency (10): eos-translations-23.9-1, archlinux-keyring-20230918-1, mutter-44.5-1, eos-bash-shared-23.9-1, python-pillow-10.0.1-1, vte-common-0.74.0-1, libdeflate-1.19-1, python-typing_extensions-4.8.0-1, imagemagick-7.1.1.16-1, vte3-0.74.0-1
:: Paketdatenbanken werden synchronisiert …
 endeavouros ist aktuell
 core ist aktuell
 extra ist aktuell
 multilib ist aktuell
:: Vollständige Systemaktualisierung wird gestartet …
Abhängigkeiten werden aufgelöst …
Nach in Konflikt stehenden Paketen wird gesucht …

Paket (14)                          Alte Version  Neue Version  Netto-Veränderung  Größe des Downloads

core/archlinux-keyring              20230821-2    20230918-1             0,00 MiB             1,14 MiB
extra/discord                       0.0.29-1      0.0.30-1               0,00 MiB            68,23 MiB
endeavouros/endeavouros-mirrorlist  23.10-1       23.12-1                0,00 MiB             0,01 MiB
endeavouros/eos-bash-shared         23.8-1        23.9-1                 0,00 MiB             0,05 MiB
endeavouros/eos-rankmirrors         2.19-1        2.20-1                 0,00 MiB             0,02 MiB
endeavouros/eos-translations        23.7-1        23.9-1                 0,00 MiB             0,08 MiB
extra/imagemagick                   7.1.1.15-4    7.1.1.16-1             0,00 MiB             8,17 MiB
extra/libdeflate                    1.18-1        1.19-1                 0,00 MiB             0,05 MiB
extra/mutter                        44.4-1        44.5-1                 0,03 MiB             2,64 MiB
extra/python-pillow                 10.0.0-2      10.0.1-1               0,00 MiB             0,78 MiB
extra/python-typing_extensions      4.7.1-1       4.8.0-1               -0,02 MiB             0,06 MiB
extra/unrar                         1:6.2.10-1    1:6.2.11-1             0,00 MiB             0,14 MiB
extra/vte-common                    0.72.2-2      0.74.0-1               0,00 MiB             0,06 MiB
extra/vte3                          0.72.2-2      0.74.0-1               0,00 MiB             0,29 MiB

Gesamtgröße des Downloads:              81,73 MiB
Gesamtgröße der installierten Pakete:  264,63 MiB
Größendifferenz der Aktualisierung:      0,02 MiB

:: Installation fortsetzen? [J/n] 
:: Pakete werden empfangen …
 python-pillow-10.0.1-1-x86_64                                                                                     796,9 KiB   619 KiB/s 00:01 [----------------------------------------------------------------------------------------] 100%
 archlinux-keyring-20230918-1-any                                                                                 1165,8 KiB   717 KiB/s 00:02 [----------------------------------------------------------------------------------------] 100%
 vte3-0.74.0-1-x86_64                                                                                              295,0 KiB   843 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 mutter-44.5-1-x86_64                                                                                                2,6 MiB  1581 KiB/s 00:02 [----------------------------------------------------------------------------------------] 100%
 unrar-1:6.2.11-1-x86_64                                                                                           140,4 KiB  1003 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 python-typing_extensions-4.8.0-1-any                                                                               64,0 KiB   711 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 eos-translations-23.9-1-any                                                                                        82,7 KiB   713 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 vte-common-0.74.0-1-x86_64                                                                                         56,7 KiB   994 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 eos-bash-shared-23.9-1-any                                                                                         52,0 KiB  1039 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 libdeflate-1.19-1-x86_64                                                                                           56,2 KiB   730 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 endeavouros-mirrorlist-23.12-1-any                                                                                 13,4 KiB   362 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 eos-rankmirrors-2.20-1-any                                                                                         20,4 KiB   106 KiB/s 00:00 [----------------------------------------------------------------------------------------] 100%
 imagemagick-7.1.1.16-1-x86_64                                                                                       8,2 MiB  2,39 MiB/s 00:03 [----------------------------------------------------------------------------------------] 100%
 discord-0.0.30-1-x86_64                                                                                            68,2 MiB  4,41 MiB/s 00:15 [----------------------------------------------------------------------------------------] 100%
 Gesamt (14/14)                                                                                                     81,7 MiB  5,27 MiB/s 00:16 [----------------------------------------------------------------------------------------] 100%
(14/14) Schlüssel im Schlüsselbund werden geprüft                                                                                              [----------------------------------------------------------------------------------------] 100%
(14/14) Paket-Integrität wird überprüft                                                                                                        [----------------------------------------------------------------------------------------] 100%
(14/14) Paket-Dateien werden geladen                                                                                                           [----------------------------------------------------------------------------------------] 100%
(14/14) Auf Dateikonflikte wird geprüft                                                                                                        [----------------------------------------------------------------------------------------] 100%
:: Pre-transaction-Hooks werden gestartet …
(1/1) Creating Timeshift snapshot before upgrade...
Using system disk as snapshot device for creating snapshots in BTRFS mode
Mounted '/dev/nvme0n1p2' at '/run/timeshift/25589/backup'
btrfs: Quotas are not enabled
Creating new backup...(BTRFS)
Saving to device: /dev/nvme0n1p2, mounted at path: /run/timeshift/25589/backup
Created directory: /run/timeshift/25589/backup/timeshift-btrfs/snapshots/2023-09-19_09-41-48
Created subvolume snapshot: /run/timeshift/25589/backup/timeshift-btrfs/snapshots/2023-09-19_09-41-48/@
Created subvolume snapshot: /run/timeshift/25589/backup/timeshift-btrfs/snapshots/2023-09-19_09-41-48/@home
Created control file: /run/timeshift/25589/backup/timeshift-btrfs/snapshots/2023-09-19_09-41-48/info.json
BTRFS Snapshot saved successfully (0s)
Tagged snapshot '2023-09-19_09-41-48': ondemand
------------------------------------------------------------------------------
Mounted '/dev/nvme0n1p2' at '/run/timeshift/25735/backup'
btrfs: Quotas are not enabled
------------------------------------------------------------------------------
Removing snapshot: 2023-09-15_07-07-30
Deleting subvolume: @home (Id:441)
Deleted subvolume: @home (Id:441)

Deleting subvolume: @ (Id:440)
Deleted subvolume: @ (Id:440)

Deleted directory: /run/timeshift/25735/backup/timeshift-btrfs/snapshots/2023-09-15_07-07-30
Removed snapshot: 2023-09-15_07-07-30
------------------------------------------------------------------------------
:: Paketänderungen werden verarbeitet …
( 1/14) Aktualisiert wird archlinux-keyring                                                                                                    [----------------------------------------------------------------------------------------] 100%
==> Füge Schlüssel aus archlinux.gpg hinzu...
==> Mache widerrufene Schlüssel im Schlüsselbund unbrauchbar...
  -> Mache Schlüssel 2 unbrauchbar...
==> Aktualisiere Trust-Datenbank...
gpg: marginals needed: 3  completes needed: 1  trust model: pgp
gpg: Tiefe: 0  gültig:   1  signiert:  12  Vertrauen: 0-, 0q, 0n, 0m, 0f, 1u
gpg: Tiefe: 1  gültig:  12  signiert:  96  Vertrauen: 0-, 0q, 0n, 12m, 0f, 0u
gpg: Tiefe: 2  gültig:  72  signiert:  27  Vertrauen: 72-, 0q, 0n, 0m, 0f, 0u
gpg: nächste "Trust-DB"-Pflichtüberprüfung am 2023-10-27
( 2/14) Aktualisiert wird discord                                                                                                              [----------------------------------------------------------------------------------------] 100%
( 3/14) Aktualisiert wird endeavouros-mirrorlist                                                                                               [----------------------------------------------------------------------------------------] 100%
Warnung: /etc/pacman.d/endeavouros-mirrorlist wurde als /etc/pacman.d/endeavouros-mirrorlist.pacnew installiert
( 4/14) Aktualisiert wird eos-translations                                                                                                     [----------------------------------------------------------------------------------------] 100%
( 5/14) Aktualisiert wird eos-bash-shared                                                                                                      [----------------------------------------------------------------------------------------] 100%
( 6/14) Aktualisiert wird eos-rankmirrors                                                                                                      [----------------------------------------------------------------------------------------] 100%
( 7/14) Aktualisiert wird imagemagick                                                                                                          [----------------------------------------------------------------------------------------] 100%
( 8/14) Aktualisiert wird libdeflate                                                                                                           [----------------------------------------------------------------------------------------] 100%
( 9/14) Aktualisiert wird mutter                                                                                                               [----------------------------------------------------------------------------------------] 100%
(10/14) Aktualisiert wird python-pillow                                                                                                        [----------------------------------------------------------------------------------------] 100%
(11/14) Aktualisiert wird python-typing_extensions                                                                                             [----------------------------------------------------------------------------------------] 100%
(12/14) Aktualisiert wird unrar                                                                                                                [----------------------------------------------------------------------------------------] 100%
(13/14) Aktualisiert wird vte-common                                                                                                           [----------------------------------------------------------------------------------------] 100%
(14/14) Aktualisiert wird vte3                                                                                                                 [----------------------------------------------------------------------------------------] 100%
:: Post-transaction-Hooks werden gestartet …
(1/9) Reloading system manager configuration...
(2/9) Reloading device manager configuration...
(3/9) Arming ConditionNeedsUpdate...
(4/9) Warn about old perl modules
(5/9) Hook to rank EndeavourOS mirrors after installing or upgrading the related mirrorlist package
==> Info: fetching https://gitlab.com/endeavouros-filemirror/PKGBUILDS/-/raw/master/endeavouros-mirrorlist/endeavouros-mirrorlist ...
==> Info: ranking EndeavourOS mirrors, please wait ...
==> Warning about https://endeavour.remi.lu/repo/$repo/$arch:
    Connection failed.
    Continuing.
==> Warning about https://mirror.jingk.ai/endeavouros/repo/$repo/$arch:
    Connection failed.
    Continuing.

==> Results of ranking EndeavourOS mirrors:


==> Writing new ranked EndeavourOS mirrorlist to /etc/pacman.d/endeavouros-mirrorlist.pacnew.
==> New mirrorlist saved.

(6/9) Compiling GSettings XML schema files...
(7/9) Updating icon theme caches...
(8/9) Checking which packages need to be rebuilt
(9/9) Updating the desktop file MIME type cache...

You can probably see that something is not right with the mirror discovery/ranking. I wanted to make sure (as much as I can) that the mirrorlist actually contains mirrors, as I have already run into that problem before, so I checked out the .pacnew mirror list. So I looked up the differences using diff, and all seemed alright:

[dromundkaas@Pure Videos]$ diff /etc/pacman.d/endeavouros-mirrorlist.pacnew /etc/pacman.d/endeavouros-mirrorlist
14a15,17
> ## Canada
> #Server = https://ca.gate.endeavouros.com/endeavouros/repo/$repo/$arch
> 
24,26d26
< ## Greece
< #Server = https://fosszone.csd.auth.gr/endeavouros/repo/$repo/$arch
< 
32c32
< #Server = https://mirrors.nxtgen.com/endeavouros-mirror/repo/$repo/$arch
---
> #Server = https://mirrors.vishnetwork.in/endeavouros/repo/$repo/$arch
57c57
< # Results of mirror ranking at (UTC) 19.09.2023 07:42:31:
---
> # Results of mirror ranking at (UTC) 11.06.2023 11:13:15:
65,79c65,79
< # https://mirror.moson.org/endeavouros/repo/$repo/$arch              1995          0.159795
< # https://mirror.alpix.eu/endeavouros/repo/$repo/$arch               1995          0.178302
< # https://de.freedif.org/EndeavourOS/repo/$repo/$arch                1995          0.229535
< # https://md.mirrors.hacktegic.com/endeavouros/repo/$repo/$arch      1995          0.324549
< # https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch         1995          0.358412
< # https://fosszone.csd.auth.gr/endeavouros/repo/$repo/$arch          1995          0.359187
< # https://fastmirror.pp.ua/endeavouros/repo/$repo/$arch              1995          0.499583
< # https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch           1995          0.661407
< # https://mirror.freedif.org/EndeavourOS/repo/$repo/$arch            1995          0.691066
< # https://mirror.albony.xyz/endeavouros/repo/$repo/$arch             1995          0.798575
< # https://mirror.funami.tech/endeavouros/repo/$repo/$arch            1995          0.959875
< # https://mirror.archlinux.tw/EndeavourOS/repo/$repo/$arch           1995          1.153128
< # https://mirrors.nxtgen.com/endeavouros-mirror/repo/$repo/$arch     1995          1.445435
< # https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch  1995          2.380897
< # https://mirrors.jlu.edu.cn/endeavouros/repo/$repo/$arch            1995          3.244969
---
> # https://mirror.moson.org/endeavouros/repo/$repo/$arch              1898          0.150835
> # https://de.freedif.org/EndeavourOS/repo/$repo/$arch                1898          0.191084
> # https://mirror.alpix.eu/endeavouros/repo/$repo/$arch               1898          0.219970
> # https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch           1898          0.711401
> # https://md.mirrors.hacktegic.com/endeavouros/repo/$repo/$arch      1897          0.217056
> # https://fastmirror.pp.ua/endeavouros/repo/$repo/$arch              1897          0.334232
> # https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch         1897          0.359975
> # https://ca.gate.endeavouros.com/endeavouros/repo/$repo/$arch       1897          0.631884
> # https://mirror.freedif.org/EndeavourOS/repo/$repo/$arch            1897          0.762404
> # https://mirror.jingk.ai/endeavouros/repo/$repo/$arch               1897          0.782125
> # https://mirror.archlinux.tw/EndeavourOS/repo/$repo/$arch           1897          0.882227
> # https://mirrors.vishnetwork.in/endeavouros/repo/$repo/$arch        1897          1.058899
> # https://mirror.funami.tech/endeavouros/repo/$repo/$arch            1897          1.117900
> # https://mirrors.jlu.edu.cn/endeavouros/repo/$repo/$arch            1897          1.504611
> # https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch  1897          1.960200
82c82
< # EndeavourOS mirrorlist, ranked by eos-rankmirrors at 19.09.2023 09:42:31.
---
> # EndeavourOS mirrorlist, ranked by eos-rankmirrors at 11.06.2023 13:13:15.
85d84
< Server = https://mirror.alpix.eu/endeavouros/repo/$repo/$arch
86a86,87
> Server = https://mirror.alpix.eu/endeavouros/repo/$repo/$arch
> Server = https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch
88,89d88
< Server = https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch
< Server = https://fosszone.csd.auth.gr/endeavouros/repo/$repo/$arch
91c90,91
< Server = https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch
---
> Server = https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch
> Server = https://ca.gate.endeavouros.com/endeavouros/repo/$repo/$arch
93,94c93
< Server = https://mirror.albony.xyz/endeavouros/repo/$repo/$arch
< Server = https://mirror.funami.tech/endeavouros/repo/$repo/$arch
---
> Server = https://mirror.jingk.ai/endeavouros/repo/$repo/$arch
96,97c95,96
< Server = https://mirrors.nxtgen.com/endeavouros-mirror/repo/$repo/$arch
< Server = https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch
---
> Server = https://mirrors.vishnetwork.in/endeavouros/repo/$repo/$arch
> Server = https://mirror.funami.tech/endeavouros/repo/$repo/$arch
98a98
> Server = https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch

Those were all the differences, and they looked alright to me. So I used Pacdiff & meld functionality from the EOS Welcome application and overwrote my mirrorlist with the new one. Afterwards, I wanted to make sure that the new list works, so I tried it:

[dromundkaas@Pure Videos]$ yay -Syu
:: Paketdatenbanken werden synchronisiert …
Fehler: Keine Datenbank konnte synchronisiert werden (Es sind keine Server für dieses Repositorium definiert)
 -> Fehler beim Aktualisieren der Datenbanken - exit status 1

That’s the status I am currently on. I think I have backups of the older mirrorlist, however, I would like to find out what the problem with my process is so I can prevent this problem in the future.

Where should I look first?

Did you do an -Syyu first?

Hello,

Did you try to rank your mirrorlist ?

eos-rankmirrors

No, I did not. Why would I? By my understanding, the yy only forces the download instead of leaving it up to the tool if it detects that a new download of the lists is necessary.

Isn’t that exactly what the upgrade did itself? It seems to be:

(5/9) Hook to rank EndeavourOS mirrors after installing or upgrading the related mirrorlist package
==> Info: fetching https://gitlab.com/endeavouros-filemirror/PKGBUILDS/-/raw/master/endeavouros-mirrorlist/endeavouros-mirrorlist ...

The upgrade update the server list, but don’t sort it, see here :
https://wiki.archlinux.org/title/mirrors#Sorting_mirrors

And the command will help you know if the mirrorlist is usable or not.

Alright, well at least it’s consistent:

[dromundkaas@Pure Videos]$ eos-rankmirrors
==> Info: fetching https://gitlab.com/endeavouros-filemirror/PKGBUILDS/-/raw/master/endeavouros-mirrorlist/endeavouros-mirrorlist ...
==> Info: ranking EndeavourOS mirrors, please wait ...
==> Warning about https://endeavour.remi.lu/repo/$repo/$arch:
    Connection failed.
    Continuing.
==> Warning about https://mirror.jingk.ai/endeavouros/repo/$repo/$arch:
    Connection failed.
    Continuing.

==> Results of ranking EndeavourOS mirrors:

######################################################
####                                              ####
###        EndeavourOS Repository Mirrorlist       ###
####                                              ####
######################################################
#### Entry in file /etc/pacman.conf:
###     [endeavouros]
###     SigLevel = PackageRequired
###     Include = /etc/pacman.d/endeavouros-mirrorlist
######################################################
### Tip: Use the 'eos-rankmirrors' program to rank
###      these mirrors or re-order them manually.
######################################################

## China
#Server = https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch
#Server = https://mirrors.jlu.edu.cn/endeavouros/repo/$repo/$arch

## Germany
#Server = https://mirror.alpix.eu/endeavouros/repo/$repo/$arch
#Server = https://de.freedif.org/EndeavourOS/repo/$repo/$arch
#Server = https://mirror.moson.org/endeavouros/repo/$repo/$arch

## Greece
#Server = https://fosszone.csd.auth.gr/endeavouros/repo/$repo/$arch

## France
#Server = https://endeavour.remi.lu/repo/$repo/$arch

## India
#Server = https://mirror.albony.xyz/endeavouros/repo/$repo/$arch
#Server = https://mirrors.nxtgen.com/endeavouros-mirror/repo/$repo/$arch

## Moldova
#Server = https://md.mirrors.hacktegic.com/endeavouros/repo/$repo/$arch

## Singapore
#Server = https://mirror.jingk.ai/endeavouros/repo/$repo/$arch
#Server = https://mirror.freedif.org/EndeavourOS/repo/$repo/$arch

## South Korea
#Server = https://mirror.funami.tech/endeavouros/repo/$repo/$arch

## Sweden
#Server = https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch

## Taiwan
#Server = https://mirror.archlinux.tw/EndeavourOS/repo/$repo/$arch

## Ukraine
#Server = https://fastmirror.pp.ua/endeavouros/repo/$repo/$arch

## United States
#Server = https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch


# Results of mirror ranking at (UTC) 19.09.2023 11:07:25:
# The following fields are shown for each mirror:
#   mirror:          The mirror address
#   update-level:    Ordinal number of the latest update (larger is newer)
#   fetch-time:      Measures the speed of the mirror (smaller is faster)
#
# mirror                                                             update-level  fetch-time
# ~~~~~~                                                             ~~~~~~~~~~~~  ~~~~~~~~~~
# https://mirror.moson.org/endeavouros/repo/$repo/$arch              1995          0.174983
# https://mirror.alpix.eu/endeavouros/repo/$repo/$arch               1995          0.175159
# https://de.freedif.org/EndeavourOS/repo/$repo/$arch                1995          0.254081
# https://fastmirror.pp.ua/endeavouros/repo/$repo/$arch              1995          0.264346
# https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch         1995          0.285087
# https://md.mirrors.hacktegic.com/endeavouros/repo/$repo/$arch      1995          0.304553
# https://mirror.albony.xyz/endeavouros/repo/$repo/$arch             1995          0.407843
# https://fosszone.csd.auth.gr/endeavouros/repo/$repo/$arch          1995          0.478698
# https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch           1995          0.686827
# https://mirror.freedif.org/EndeavourOS/repo/$repo/$arch            1995          0.752566
# https://mirror.funami.tech/endeavouros/repo/$repo/$arch            1995          0.907682
# https://mirror.archlinux.tw/EndeavourOS/repo/$repo/$arch           1995          1.114434
# https://mirrors.nxtgen.com/endeavouros-mirror/repo/$repo/$arch     1995          1.291251
# https://mirrors.jlu.edu.cn/endeavouros/repo/$repo/$arch            1995          1.545239
# https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch  1995          2.065163

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# EndeavourOS mirrorlist, ranked by eos-rankmirrors at 19.09.2023 13:07:25.
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Server = https://mirror.moson.org/endeavouros/repo/$repo/$arch
Server = https://mirror.alpix.eu/endeavouros/repo/$repo/$arch
Server = https://de.freedif.org/EndeavourOS/repo/$repo/$arch
Server = https://fastmirror.pp.ua/endeavouros/repo/$repo/$arch
Server = https://ftp.acc.umu.se/mirror/endeavouros/repo/$repo/$arch
Server = https://md.mirrors.hacktegic.com/endeavouros/repo/$repo/$arch
Server = https://mirror.albony.xyz/endeavouros/repo/$repo/$arch
Server = https://fosszone.csd.auth.gr/endeavouros/repo/$repo/$arch
Server = https://mirrors.gigenet.com/endeavouros/repo/$repo/$arch
Server = https://mirror.freedif.org/EndeavourOS/repo/$repo/$arch
Server = https://mirror.funami.tech/endeavouros/repo/$repo/$arch
Server = https://mirror.archlinux.tw/EndeavourOS/repo/$repo/$arch
Server = https://mirrors.nxtgen.com/endeavouros-mirror/repo/$repo/$arch
Server = https://mirrors.jlu.edu.cn/endeavouros/repo/$repo/$arch
Server = https://mirrors.tuna.tsinghua.edu.cn/endeavouros/repo/$repo/$arch
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

==> Moving old EndeavourOS mirrorlist to /etc/pacman.d/endeavouros-mirrorlist.2023.09.19-13.07.25.
==> Writing new ranked EndeavourOS mirrorlist to /etc/pacman.d/endeavouros-mirrorlist.
Root Passwort: 
==> New mirrorlist saved.

[dromundkaas@Pure Videos]$ yay -Syu
[sudo] Passwort für dromundkaas: 
:: Paketdatenbanken werden synchronisiert …
Fehler: Keine Datenbank konnte synchronisiert werden (Es sind keine Server für dieses Repositorium definiert)
 -> Fehler beim Aktualisieren der Datenbanken - exit status 1

Maybe the problem is not the Endeavour mirrorlist, but the Arch one.
Try to renew the Arch one :

reflector --sort score -p https -n 10 | sudo tee /etc/pacman.d/mirrorlist

That seems to fix the issue. Thanks. Which leaves one question: Why does that happen after the upgrade mentioned in the original post? What is breaking or invalidating the arch mirror list?

I don’t know, the last update of the pacman-mirrorlist package was the 20 August. Nothing should corrupt these mirrorlist files.

-Syyu - rewrites the database files as you are now pointed at a new mirror! Without it you are pointing at the wrong repo:

-y, --refresh
Download a fresh copy of the master package list from the server(s) defined in pacman.conf(5). This should typically be used each time you use
–sysupgrade or -u. Passing two --refresh or -y flags will force a refresh of all package lists even if they appear to be up to date.

Don’t know why you did a yay -Syu. Just running yay is enough unless you’re updating your system after a very long time.

If you’re updating the system after a very long it is best to update both mirror lists and the keyrings as well.
reflector --sort score -p https -n 10 | sudo tee /etc/pacman.d/mirrorlist
eos-rankmirrors
sudo pacman -Sy archlinux-keyring endeavouros-keyring
then
yay or yay -Syu

Please show the output of these commands:

cat /etc/pacman.conf > /tmp/foobar
cat /etc/pacman.d/mirrorlist >> /tmp/foobar
cat /etc/pacman.d/endeavouros-mirrorlist >> /tmp/foobar
cat /tmp/foobar | eos-sendlog

And sorry, I will be out of my home office tonight, will probably be here much later today, or tomorrow.

Does command

sudo pacman -Syu

work as expected?

To me -Syu download only the changes in your database, -Syyu download all the database, it’s not a question of repo.