How to compare kernel (or other) version numbers in Ansible

问题

For a role I'm developing I need to verify that the kernel version is greater than a particular version.

I've found the ansible_kernel value, but is there an easy way to compare this to other versions? I thought I might manually explode the version string on the '.'s & compare the numbers, but I can't even find a friendly filter to explode the version string out, so I'm at a loss.

Thanks in advance.

T

回答1:

There is a test for it:

{{ ansible_distribution_version | version_compare('12.04', '>=') }}

{{ sample_version_var | version_compare('1.0', operator='lt', strict=True) }}

回答2:

To Print the host IP address if the kernel version is less than 3

Ansible Version : 2.0.0.2

---
- hosts: all
  vars:
   kernel_version: "{{ ansible_kernel }}"
  tasks:
   - name: 'kernel version from facts'
     debug:
      msg: '{{ansible_all_ipv4_addresses}} {{ansible_kernel}}'
     when: ansible_kernel |  version_compare('3','<')

**

In 2.5 version_compare was renamed to version

**

回答3:

Have you thought of using shell module instead? for example:

   - name: Get Kernel version
     shell: uname -r | egrep '^[0-9]*\.[0-9]*' -o
     register: kernel_shell_output

   - debug: msg="{{ kernel_shell_output.stdout}}"

   - name: Add cstate and reboot bios if kernel is 4.8
     shell: echo "do what yo need to do"
     when: kernel_shell_output.stdout == "4.8"

来源：https://stackoverflow.com/questions/39779802/how-to-compare-kernel-or-other-version-numbers-in-ansible