rhel prevalidate

prevalidate.yml

---
# User Input Variables (extra vars)
# memory_threshold: Value in MB. If free memory is less than this value then stop prevalidation
# swap_threshold: Value in MB. If free swap is less than this value then stop prevalidation
# disk_threshold: Value in MB. If free disk space is less than this value then stop prevalidation
# change selected host group to match requirements
- hosts: all
  # ensure gather facts is on
  gather_facts: yes
  vars:
    memory_threshold: 100
    swap_threshold: 1000
    disk_threshold: 1000
  tasks:
    - name: "check if memory is below {{ memory_threshold }} MB"
      assert:
        that: "ansible_memory_mb.real.free  > memory_threshold "
        msg: "Free memory is {{ ansible_memory_mb.real.free }} MB and is less than the pre-validation threshold of {{ memory_threshold }} MB"

    - name: "check if swap is below {{ swap_threshold }} MB"
      assert:
        that: "ansible_memory_mb.swap.free  > swap_threshold"
        msg: "Free Swap space is {{ ansible_memory_mb.swap.free }} MB and is less than the pre-validation threshold of {{ swap_threshold }} MB"

    - name: convert disk_threshold from Mb to Kb
      set_fact:
        disk_threshold_in_kb: "{{ disk_threshold * 1024  }}"

    - name: check that all disk sizes are not below {{ disk_threshold }} MB"
      assert:
        that: "item.size_available  > disk_threshold_in_kb|int "
        msg: "Mountpoint: {{ item.mount }} is less than {{ disk_threshold }} MB available"
      with_items: "{{ ansible_mounts }}"


    - name: full fstab output
      shell: cat /etc/fstab
      register: full_fstab_output
      changed_when: false

    - name: capture etc/fstab output
      shell: awk '!/^#/ { print $2 }' /etc/fstab
      register: fstab_output
      changed_when: false

    - name: set fstab entries into a variable called fstab_mountpoints.
      set_fact:
        fstab_mountpoints: "{{ fstab_output.stdout_lines | difference(['','swap']) }}"

    - name: get list of mount points
      set_fact:
        devices_mounted: "{{ ansible_mounts | map(attribute='mount') | list }}"

    - name: get a list of fstab mounts that are not active
      set_fact:
        mounts_not_active: "{{ fstab_mountpoints | difference(devices_mounted) }}"

    - name: fail if not all fstab mounts are not active
      assert:
        that: "mounts_not_active == []"
        msg: "Some mounts in /etc/fstab are not active - mount point list {{ mounts_not_active }}"

    - name: use yum check-updates because yum-utils may be not installed on these RHEL systems
      shell: yum check-updates -q
      register: yum_updates
      failed_when: yum_updates.rc != 100
      changed_when: false

    - name: list packages that need to be updated in the package_updates variable
      set_fact:
        package_updates: "{{ yum_updates.stdout_lines | difference(['']) }}"

    - name: commands in this block require escalated privileges
      block:
      - name: get last yum command run,  start , end date and installed packages
        shell: yum history info | grep -e "Begin time" -e "Command Line" -e "Installed" -e "User"
        changed_when: false
        register: last_yum_command

      - name: clean all yum caches. Must be a become user to execute this
        shell: yum clean all
        changed_when: false
      become: true

    - name: grab df output for printing to the report
      shell: df -Ph
      register: df_output
      changed_when: false

    # Generate a report. Recommend using email as the notification mechanism or
    # copying to a SCP/NFS share for further review.
    # In this example, report is copied to the ansible server- not recommended. Just doing it for demo purposes.
    # If using Ansible Tower use the recommended notification mechanism instead.
    - name: generate a report
      template:
        src: prevalidation-report.j2
        dest: /tmp/{{inventory_hostname}}_prevalidation-report.txt

    - name: |
        fetch the report and place on the local ansible server.
        Do not do this step if running this task from Ansible Tower.
        It will break the Tower Project repository Sync process
      fetch:
        src: /tmp/{{inventory_hostname}}_prevalidation-report.txt
        dest: "./{{inventory_hostname}}_prevalidation-report.txt"
        flat: yes

prevalidation_report.j2

PRE-VALIDATION REPORT
=====================

Hostname: {{ inventory_hostname }}
Kernel Version: {{ ansible_kernel }}
Packages to Update: {{ package_updates |length }}

Disk Layout and Sizing:
------------------------

{{ df_output.stdout }}

/etc/fstab
----------

{{ full_fstab_output.stdout }}

Last Yum Command
---------------

{{ last_yum_command.stdout }}