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--- lab:stack_of_nucs:ansible_playbook_-_update [2023/05/13 19:45] – [Optional] user
+++ lab:stack_of_nucs:ansible_playbook_-_update [2024/05/06 02:12] (current) – removed user
@@ Line 1: / Line 1: @@
-====== Ansible Playbook - Update ======
-In the [[discover_and_add_to_inventory|previous step]] we discovered and added the IP address of all our nodes to the file on [[NUC 2]]: ''/home/ansible/my-project/hosts''
-Our first Ansible playbook will be to update Ubuntu packages on all the worker nodes.
-Purpose:
-  * Demonstrate a very useful playbook
-  * Update all our nodes to the latest code
-====== Step 1 - Connect to the Ansible Control Node ======
-From [[NUC 1]], log in to the Ansible control node, [[NUC 2]].
-====== Step 2 - Create the Playbook ======
-Create file ''/home/ansible/my-project/update.yml''
-<file yaml update.yml>
----
-- hosts: nodes
-  become: true
-  become_user: root
-  tasks:
-    - name: Update apt repo and cache on all Debian/Ubuntu boxes
-      apt: update_cache=yes force_apt_get=yes cache_valid_time=3600
-    - name: Upgrade all packages on servers
-      apt: upgrade=dist force_apt_get=yes
-    - name: Check if a reboot is needed on all servers
-      register: reboot_required_file
-      stat: path=/var/run/reboot-required get_md5=no
-    - name: Reboot the box if kernel updated
-      reboot:
-        msg: "Reboot initiated by Ansible for kernel updates"
-        connect_timeout: 5
-        reboot_timeout: 300
-        pre_reboot_delay: 0
-        post_reboot_delay: 30
-        test_command: uptime
-      when: reboot_required_file.stat.exists
-</file>
-====== Step 3 - Test the Playbook ======
-''ansible-playbook -i hosts update.yml''
-====== DNS Name Resolution Issues======
-It's not great, but some servers are inconsistent in resolving DNS names using DHCP.
-Here is a quick fix I have used in the past:
-''ansible -i hosts all -a dhclient''
-This can get you name resolution, but you many have two IP addresses!
-Current things to test better solutions:
-  * ''sudo netplan apply''
-  * ''sudo reboot''
-====== Next Step ======
-Congratulations you just updated your nodes! Next is your second Ansible playbook - [[Ansible Playbook - CMOS]].
-====== Optional ======
-===== Faster Bootup Times with WiFi Only =====
-Set the ethernet interface to be "optional" on the nodes so they will boot faster; they normally wait for the network to come up on the wired interface. Since we are on WiFi only, the interface will never come up.
-Steps:
-  - Create file /home/ansible/my-project/ethernetoptional.yml
-    * <file yaml ethnetoptional.yml>
----
-- hosts: nodes
-  become: true
-  become_user: root
-  tasks:
-    - name: Set ethernet interface to optional
-      lineinfile:
-        path: /etc/netplan/00-installer-config.yaml
-        insertafter: "dhcp4: true"
-        line: "      optional: true"
-    - name: Apply netplan
-      command: netplan apply
-      ignore_errors: true
-</file>
-  - Test the playbook
-    * ''ansible-playbook -i hosts ethernetoptional.yml''
-===== Check the WiFi on the NUC =====
-Sometimes in my Lab testing I find a NUCs that seem slowing or become unresponsive. This can actually be due to a poor WiFi connection!
-  - Create the playbook check-wifi.yml
-    * <file yaml check-wifi.yml>
----
-- name: Check wifi strength
-  hosts: all
-  remote_user: ansible
-  become: true
-  tasks:
-    - name: Make sure wireless-tools is installed
-      apt:
-        name: wireless-tools
-        state: present
-    - name: Gather wifi strength
-      shell: "iwconfig | grep Quality"
-      register: wifi
-      changed_when: false
-    - name: Display wifi strength
-      debug:
-        msg: "{{ item }}"
-      with_items: "{{ wifi.stdout_lines }}"
-</file>
-  - Run it: ''ansible-playbook -i hosts check-wifi.yml''
-  - If all the NUCs are in the same place but one is much weaker than the others
-    * check the antennas are connected to the Wifi card
-    * does a different wifi card improve the connection?