MCS doesn't survive minor upgrade.

apt-get -y install ./mariadb-client-core-10.5_10.5.5+maria~bionic_amd64.deb ./mariadb-client-10.5_10.5.5+maria~bionic_amd64.deb ./mariadb-server-core-10.5_10.5.5+maria~bionic_amd64.deb ./mariadb-common_10.5.5+maria~bionic_all.deb ; apt-get -y install ./mariadb-server-10.5_10.5.5+maria~bionic_amd64.deb ; apt-get -y install ./mariadb-plugin-columnstore_10.5.5+maria~bionic_amd64.deb

Reading package lists... Done

Building dependency tree       

Reading state information... Done

Note, selecting 'mariadb-client-core-10.5' instead of './mariadb-client-core-10.5_10.5.5+maria~bionic_amd64.deb'

Note, selecting 'mariadb-client-10.5' instead of './mariadb-client-10.5_10.5.5+maria~bionic_amd64.deb'

Note, selecting 'mariadb-server-core-10.5' instead of './mariadb-server-core-10.5_10.5.5+maria~bionic_amd64.deb'

Note, selecting 'mariadb-common' instead of './mariadb-common_10.5.5+maria~bionic_all.deb'

The following packages were automatically installed and are no longer required:

  expect galera-4 libcgi-fast-perl libcgi-pm-perl libencode-locale-perl libfcgi-perl libhtml-parser-perl libhtml-tagset-perl libhtml-template-perl libhttp-date-perl libhttp-message-perl libio-html-perl libjemalloc1

  liblwp-mediatypes-perl libsnappy1v5 libtcl8.6 libtimedate-perl liburi-perl linux-gcp-5.3-headers-5.3.0-1026 socat tcl-expect tcl8.6

Use 'apt autoremove' to remove them.

The following packages will be REMOVED:

  mariadb-server-10.5

The following packages will be upgraded:

  mariadb-client-10.5 mariadb-client-core-10.5 mariadb-common mariadb-server-core-10.5

4 upgraded, 0 newly installed, 1 to remove and 34 not upgraded.

Need to get 0 B/8836 kB of archives.

After this operation, 71.0 MB disk space will be freed.

Get:1 /home/roman_nozdrin_mariadb_com/mariadb-common_10.5.5+maria~bionic_all.deb mariadb-common all 1:10.5.5+maria~bionic [4124 B]

Get:2 /home/roman_nozdrin_mariadb_com/mariadb-client-core-10.5_10.5.5+maria~bionic_amd64.deb mariadb-client-core-10.5 amd64 1:10.5.5+maria~bionic [764 kB]

Get:3 /home/roman_nozdrin_mariadb_com/mariadb-client-10.5_10.5.5+maria~bionic_amd64.deb mariadb-client-10.5 amd64 1:10.5.5+maria~bionic [1550 kB]

Get:4 /home/roman_nozdrin_mariadb_com/mariadb-server-core-10.5_10.5.5+maria~bionic_amd64.deb mariadb-server-core-10.5 amd64 1:10.5.5+maria~bionic [6518 kB]

(Reading database ... 214912 files and directories currently installed.)

Removing mariadb-server-10.5 (1:10.5.4+maria~bionic) ...

(Reading database ... 214787 files and directories currently installed.)

Preparing to unpack .../mariadb-common_10.5.5+maria~bionic_all.deb ...

Unpacking mariadb-common (1:10.5.5+maria~bionic) over (1:10.5.4+maria~bionic) ...

dpkg: considering removing mariadb-client-10.5 in favour of mariadb-client-core-10.5 ...

dpkg: yes, will remove mariadb-client-10.5 in favour of mariadb-client-core-10.5

Preparing to unpack .../mariadb-client-core-10.5_10.5.5+maria~bionic_amd64.deb ...

Unpacking mariadb-client-core-10.5 (1:10.5.5+maria~bionic) over (1:10.5.4+maria~bionic) ...

Selecting previously unselected package mariadb-client-10.5.

Preparing to unpack .../mariadb-client-10.5_10.5.5+maria~bionic_amd64.deb ...

Unpacking mariadb-client-10.5 (1:10.5.5+maria~bionic) ...

Preparing to unpack .../mariadb-server-core-10.5_10.5.5+maria~bionic_amd64.deb ...

Unpacking mariadb-server-core-10.5 (1:10.5.5+maria~bionic) over (1:10.5.4+maria~bionic) ...

Setting up mariadb-common (1:10.5.5+maria~bionic) ...

Notice: configure-symlinks trigger could not be called.

Please manually create symlinks by running: 

  mv -f /etc/mysql/my.cnf /etc/mysql/my.cnf.old

  ln -sf mariadb.cnf /etc/mysql/my.cnf

Setting up mariadb-client-core-10.5 (1:10.5.5+maria~bionic) ...

Setting up mariadb-client-10.5 (1:10.5.5+maria~bionic) ...

Setting up mariadb-server-core-10.5 (1:10.5.5+maria~bionic) ...

Processing triggers for man-db (2.8.3-2ubuntu0.1) ...

Reading package lists... Done

Building dependency tree       

Reading state information... Done

Note, selecting 'mariadb-server-10.5' instead of './mariadb-server-10.5_10.5.5+maria~bionic_amd64.deb'

The following packages were automatically installed and are no longer required:

  expect libjemalloc1 libsnappy1v5 libtcl8.6 linux-gcp-5.3-headers-5.3.0-1026 tcl-expect tcl8.6

Use 'apt autoremove' to remove them.

Suggested packages:

  mailx mariadb-test tinyca

The following NEW packages will be installed:

  mariadb-server-10.5

0 upgraded, 1 newly installed, 0 to remove and 34 not upgraded.

Need to get 0 B/4257 kB of archives.

After this operation, 67.8 MB of additional disk space will be used.

Get:1 /home/roman_nozdrin_mariadb_com/mariadb-server-10.5_10.5.5+maria~bionic_amd64.deb mariadb-server-10.5 amd64 1:10.5.5+maria~bionic [4257 kB]

Preconfiguring packages ...

Selecting previously unselected package mariadb-server-10.5.

(Reading database ... 214787 files and directories currently installed.)

Preparing to unpack .../mariadb-server-10.5_10.5.5+maria~bionic_amd64.deb ...

/var/lib/mysql: found previous version 10.5

Unpacking mariadb-server-10.5 (1:10.5.5+maria~bionic) ...

Setting up mariadb-server-10.5 (1:10.5.5+maria~bionic) ...

Processing triggers for man-db (2.8.3-2ubuntu0.1) ...

Processing triggers for ureadahead (0.100.0-21) ...

Processing triggers for systemd (237-3ubuntu10.39) ...

Reading package lists... Done

Building dependency tree       

Reading state information... Done

Note, selecting 'mariadb-plugin-columnstore' instead of './mariadb-plugin-columnstore_10.5.5+maria~bionic_amd64.deb'

The following package was automatically installed and is no longer required:

  linux-gcp-5.3-headers-5.3.0-1026

Use 'apt autoremove' to remove it.

The following NEW packages will be installed:

  mariadb-plugin-columnstore

0 upgraded, 1 newly installed, 0 to remove and 34 not upgraded.

Need to get 0 B/6350 kB of archives.

After this operation, 29.9 MB of additional disk space will be used.

Get:1 /home/roman_nozdrin_mariadb_com/mariadb-plugin-columnstore_10.5.5+maria~bionic_amd64.deb mariadb-plugin-columnstore amd64 1:10.5.5+maria~bionic [6350 kB]

Selecting previously unselected package mariadb-plugin-columnstore.

(Reading database ... 214911 files and directories currently installed.)

Preparing to unpack .../mariadb-plugin-columnstore_10.5.5+maria~bionic_amd64.deb ...

Unpacking mariadb-plugin-columnstore (1:10.5.5+maria~bionic) ...

Setting up mariadb-plugin-columnstore (1:10.5.5+maria~bionic) ...

Configuration file '/etc/columnstore/Columnstore.xml'

 ==> Modified (by you or by a script) since installation.

 ==> Package distributor has shipped an updated version.

   What would you like to do about it ?  Your options are:

    Y or I  : install the package maintainer's version

    N or O  : keep your currently-installed version

      D     : show the differences between the versions

      Z     : start a shell to examine the situation

 The default action is to keep your current version.

*** Columnstore.xml (Y/I/N/O/D/Z) [default=N] ? Y

Installing new version of config file /etc/columnstore/Columnstore.xml ...

Installing new version of config file /etc/mysql/mariadb.conf.d/columnstore.cnf ...

checking for engine columnstore...

columnstore doesn't exist

There was an error installing MariaDB ColumnStore engine plugin. Continue to install the engine though. \ 

Please resolve the issues and run necessary scripts manually.

Populating the engine initial system catalog.

Processing triggers for mariadb-server-10.5 (1:10.5.5+maria~bionic) ...

Processing triggers for libc-bin (2.27-3ubuntu1.2) ...

root@drrtuy-u18-2:/home/roman_nozdrin_mariadb_com# ls /tmp/