15. Ansible management LXC setup.¶

Pickup one of the Ansible management containers, lxcans01 – lxcans05. It would be preferable if you match the number with that of your lxc container.

The user name and password are the same as on your lxc.

Install ansible:

sudo apt install ansible

Work as user hostadm in all the steps below.

On lxcans# container, download Ansible.tgz with the ceph related playbooks:

wget https://linuxcourse.rutgers.edu/Winlab_Internship_2023/html/files/Ansible.tgz

Untar the archive:

tar -zxvf Ansible.tgz
cd Ansible

15.1. Get your node reimaged through FOG¶

Schedule FOG for image deployment on your node.

Reboot the node to boot from network.

15.2. Passwordless SSH login setup to your node and LXC container.¶

Change the hosts assignment in hosts= ... line in script ssh_hostadm_key.sh. Put your lxc and your node name there.

Run the script:

./ssh_hostadm_key.sh

Give the password for the node access by hostadm.

This should set passwordless ssh access to your node and lxc container. Try ssh to them from your lxcans contasiner to verify you can login without password.

15.3. Modify the inventory file, hosts.ini¶

Put the correct node name in hosts.ini

15.4. Passwordless sudo¶

Run the ansible playbook to setup passwordless sudo on the node:

ansible-playbook sudoers.yml --ask-become-pass

Provide the login password for hostadm to the node.

This should setup passwordless sudo for hostadm on the node. SSH to the node and check it.

15.5. Fix the hostname on the node.¶

Run the ansible playbook for fixing the hostname:

ansible-playbook fix_hostname_tasks.yml

SSH to the node to check if the hostname is fixed.

15.6. Deploy Ceph on the node.¶

Run the playbook:

ansible-playbook ceph_one_node.yml

If it fails at the Dashboard setup, re-run it again.

15.7. Steps to create Ansible playbook for CephFS mounting¶

Add your lxc container to the inventory file, hosts.ini For example

In directory Ansible, create new file mount_ceph.yml with a play for ceph_mounts and role mount_ceph:

mount_ceph.yml:

---
- name: Mount CephFS on the clients
  hosts: ceph_mounts

  roles:
    - mount_ceph

Create directory tree under Ansible: roles/mount_ceph/tasks, roles/mount_ceph/files
In directory roles/mount_ceph/tasks, create file main.yml, and start composing the tasks in main.yml
You’ll need to base the tasks on the following modules:
- ansible.builtin.shell
- ansible.builtin.fetch
- ansible.builtin.copy
File ceph.conf needs to be fetched from the node. Then it needs to be copied onto your lxc container.
Similarly, you’ll need to copy the key.
Check your playbook for syntactic errors:

ansible-playbook  mount_ceph.yml --syntax-check

If no errors show up, run the playbook:

ansible-playbook mount_ceph.yml

Winlab Summer 2023 Internship project

Ansible management LXC setup.

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