Preparing to unpack .../libssl1.1_1.1.1-1ubuntu2.1~18.04.4_s390x.deb ... Unpacking libssl1.1:s390x (1.1.1-1ubuntu2.1~18.04.4) ... Selecting previously unselected package openssl. Preparing to unpack .../openssl_1.1.1-1ubuntu2.1~18.04.4_s390x.deb ... Unpacking openssl (1.1.1-1ubuntu2.1~18.04.4) ... Processing triggers for libc-bin (2.27-3ubuntu1) ... Setting up libssl1.1:s390x (1.1.1-1ubuntu2.1~18.04.4) ... debconf: unable to initialize frontend: Dialog debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot  be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 76.) debconf: falling back to frontend: Readline debconf: unable to initialize frontend: Readline debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine  module) (@INC contains: /etc/perl /usr/local/lib/s390x-linux-gnu/perl/5.26.1  /usr/local/share/perl/5.26.1 /usr/lib/s390x-linux-gnu/perl5/5.26 /usr/share/perl5  /usr/lib/s390x-linux-gnu/perl/5.26 /usr/share/perl/5.26 /usr/local/lib/site_perl  /usr/lib/s390x-linux-gnu/perl-base) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line  7.) debconf: falling back to frontend: Teletype Setting up openssl (1.1.1-1ubuntu2.1~18.04.4) ... Processing triggers for libc-bin (2.27-3ubuntu1) ... root@38d485c33e24:/#  openssl req \ > -newkey rsa:4096 -nodes -sha256 \ > -keyout /tmp/certs/docker_domain.key \ > -x509 -days 365 -out /tmp/certs/docker_domain.crt Can't load /root/.rnd into RNG 4396277008160:error:2406F079:random number generator:RAND_load_file:Cannot open  file:../crypto/rand/randfile.c:88:Filename=/root/.rnd Generating a RSA private key ..............................................................++++ ..............................................................++++ writing new private key to '/tmp/certs/docker_domain.key' ----- You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, If you enter '.', the field will be left blank. ----- 134  Getting started with z/OS Container Extensions 4. Run the following commands connected to create the TLS certificates. a. To generate your own certificate, run the following commands: mkdir -p /tmp/certs openssl req \ -newkey rsa:4096 -nodes -sha256 \ -keyout /tmp/certs/docker_domain.key \ -x509 -days 365 -out /tmp/certs/docker_domain.crt Note:  Be sure to use the zCX hostname as Common Name. In Example 6-18, ensure that you respond to the questions with information that is accurate  for your system and location. We highlighted in bold the responses that were valid for our  environment. Example 6-28 Using openssl to create the TLS certificate