diff --git a/CHANGELOG.md b/CHANGELOG.md
index f8bcf2a..c6b777c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,8 @@ This file is used to list changes made in each version of the postfix cookbook.
 
 ## Unreleased
 
+- resolved cookstyle error: test/integration/helpers/serverspec/spec_helper.rb:9:21 convention: `Style/FileRead`
+
 ## 6.0.4 - *2021-08-19*
 
 ## 6.0.3 - *2021-08-19*
diff --git a/kitchen.dokken.yml b/kitchen.dokken.yml
index 1d3b9e2..331c709 100644
--- a/kitchen.dokken.yml
+++ b/kitchen.dokken.yml
@@ -21,15 +21,11 @@ platforms:
     driver:
       image: dokken/debian-9
       pid_one_command: /bin/systemd
-      intermediate_instructions:
-        - RUN /usr/bin/apt-get update
 
   - name: debian-10
     driver:
       image: dokken/debian-10
       pid_one_command: /bin/systemd
-      intermediate_instructions:
-        - RUN /usr/bin/apt-get update
 
   - name: centos-7
     driver:
@@ -50,24 +46,18 @@ platforms:
     driver:
       image: dokken/ubuntu-16.04
       pid_one_command: /bin/systemd
-      intermediate_instructions:
-        - RUN /usr/bin/apt-get update
 
   - name: ubuntu-18.04
     driver:
       image: dokken/ubuntu-18.04
       pid_one_command: /bin/systemd
-      intermediate_instructions:
-        - RUN /usr/bin/apt-get update
 
   - name: ubuntu-20.04
     driver:
       image: dokken/ubuntu-20.04
       pid_one_command: /bin/systemd
-      intermediate_instructions:
-        - RUN /usr/bin/apt-get update
 
   - name: opensuse-leap-15
     driver:
       image: dokken/opensuse-leap-15
-      pid_one_command: /bin/systemd
+      pid_one_command: /usr/lib/systemd/systemd
diff --git a/test/integration/helpers/serverspec/spec_helper.rb b/test/integration/helpers/serverspec/spec_helper.rb
index cbd00f1..f5629e6 100644
--- a/test/integration/helpers/serverspec/spec_helper.rb
+++ b/test/integration/helpers/serverspec/spec_helper.rb
@@ -6,7 +6,7 @@ set :path, '/sbin:/usr/local/sbin:$PATH'
 def family
   fam = 'solaris2'
   return fam unless File.exist? '/etc/release'
-  fam = 'omnios' if File.open('/etc/release').read =~ /^\s*(OmniOS)/
+  fam = 'omnios' if File.read('/etc/release') =~ /^\s*(OmniOS)/
   fam
 end