Conversion from CentOS 7 to AlmaLinux 8 fails: ibssl.so.1.1: cannot open shared object file: No such file or directory

Symptoms

• Conversion from CentOS 7 to AlmaLinux 8 fails during the preparation check. The following error message is logged in  /var/log/plesk/centos2alma.log:

  CONFIG_TEXT: /usr/sbin/postconf: error while loading shared libraries: libssl.so.1.1: cannot open shared object file: No such file or directory
  ERROR: Command '['/usr/sbin/postconf', '-dh', 'mail_version']' returned non-zero exit status 127.
  exit status 1

• The following error message is shown on the Home page in Plesk:

  PLESK_ERROR: Error: New configuration files for the Apache web server were not created due to the errors in configuration templates: /usr/sbin/nginx: error while loading shared libraries: libssl.so.1.1: cannot open shared object file: No such file or directory.

Cause

openssl11-libs package is missing in the system:

# rpm -qa | grep openssl11-libs
alt-openssl11-libs-1.1.1w-2.el7.x86_64

Resolution

1. Connect to the server via SSH.

2. Install openssl11-libs package:

   # yum install openssl11-libs

3. Rerun Plesk Update to make sure all Plesk packages are installed and up-to-date:

   # plesk installer update