From b3f6c3f830fd2a68fde33eabffa92bb8e0663787 Mon Sep 17 00:00:00 2001 From: DarkSun Date: Tue, 12 Jan 2021 05:02:36 +0800 Subject: [PATCH] =?UTF-8?q?=E9=80=89=E9=A2=98[tech]:=2020210111=20Deploy?= =?UTF-8?q?=20Ceph=20in=20a=20Raspberry=20Pi=20cluster?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit sources/tech/20210111 Deploy Ceph in a Raspberry Pi cluster.md --- ...1 Deploy Ceph in a Raspberry Pi cluster.md | 232 ++++++++++++++++++ 1 file changed, 232 insertions(+) create mode 100644 sources/tech/20210111 Deploy Ceph in a Raspberry Pi cluster.md diff --git a/sources/tech/20210111 Deploy Ceph in a Raspberry Pi cluster.md b/sources/tech/20210111 Deploy Ceph in a Raspberry Pi cluster.md new file mode 100644 index 0000000000..b41655d671 --- /dev/null +++ b/sources/tech/20210111 Deploy Ceph in a Raspberry Pi cluster.md @@ -0,0 +1,232 @@ +[#]: collector: (lujun9972) +[#]: translator: ( ) +[#]: reviewer: ( ) +[#]: publisher: ( ) +[#]: url: ( ) +[#]: subject: (Deploy Ceph in a Raspberry Pi cluster) +[#]: via: (https://opensource.com/article/21/1/ceph-raspberry-pi) +[#]: author: (AJ Canlas https://opensource.com/users/ajscanlas) + +Deploy Ceph in a Raspberry Pi cluster +====== +Install Ceph storage using ceph-ansible and deploy it in a Raspberry Pi +cluster. +![Vector, generic Raspberry Pi board][1] + +[Ceph][2] is an open source software storage platform that provides object, block, and filesystem storage in a unified storage cluster. I first used Ceph when I [integrat][3][ed it with OpenStack][3]. At first, I was confused about why I should use Ceph since storage devices are widely available. But after using it for more than three years, the platform's stability and integrity have proven its value again and again. + +This article will show you how to install Ceph using [ceph-ansible][4] (an officially supported Ansible playbook for Ceph) and deploy it in a Raspberry Pi cluster. + +**Materials:** + + 1. Four Raspberry Pi 4B 4GB models + 2. Four 32GB microSD cards (boot OS) + 3. Four Raspberry Pi cases with fans and heatsinks (very important) + 4. Four Raspberry Pi chargers + 5. Six 32GB USB flash drives (for the Ceph OSD nodes) + + + +**Architecture:** + +![Project architecture][5] + +(Aaron John Canlas, [CC BY-SA 4.0][6]) + +Regarding the configuration: + + * Both the front-end and back-end networks are in the same subnet + * The [Ceph Monitor][7] software uses a Raspberry Pi 4B with 4GB RAM + * The [Ceph OSD][8] nodes use the same Raspberry Pi model but with two USB flash drives for the OSD disks + + + +### Deploy Ceph using ceph-ansible + +Using Ceph's Ansible repository makes the deployment smooth and simple. + +#### 1\. Copy ssh keys to all servers + +I have a common user called `cephadmin` on all servers (each Raspberry Pi is a server in this context). The `cephadmin` user is configured with passwordless `sudo` to make things easier. + +After generating a key using `ssh-keygen`, deploy all keys using `ssh-copy-id`. + +I use a Bash for-loop because I'm using consistent and incremental hostnames: + + +``` +$ for i in {0..3}; \ +  do ssh-copy-id cephadmin@rpi4b4-$i; \ +done +``` + +You need to accept and enter your password on each one, but you can automate this with `expect`. + +#### 2\. Clone ceph-ansible and install requirements + +Install Git to clone the repository: + + +``` +`$ sudo yum install git -y` +``` + +Clone the ceph-ansible repository: + + +``` +$ git clone +$ cd ceph-ansible/ +``` + +I'm using an AArch64 build of CentOS 7, so I must install some required packages before continuing. + +First, Python pip: + + +``` +`$ sudo yum install python3-pip -y` +``` + +Then the packages ceph-ansible needs: + + +``` +`$ sudo yum install python3-devel libffi-devel openssl-devel -y` +``` + +Finally, the requirements `ceph-ansible` needs: + + +``` +`$ pip3 install -r requirements.txt --user` +``` + +I received this error: + + +``` +You are linking against OpenSSL 1.0.2, which is no longer supported by the OpenSSL project. +To use this version of cryptography you need to upgrade to a newer version of OpenSSL. For +this version only you can also set the environment variable +CRYPTOGRAPHY_ALLOW_OPENSSL_102 to allow OpenSSL 1.0.2. +``` + +This may be related to the architecture, because I can't replicate the error in a CentOS 7 virtual machine. + +For deployment, export `CRYPTOGRAPHY_ALLOW_OPENSSL_102` to `True` so that Ansible can run: + + +``` +`$ export CRYPTOGRAPHY_ALLOW_OPENSSL_102=True` +``` + +#### 3\. Configure ceph-ansible for deployment + +Now you're ready to deploy Ceph using ceph-ansible. + +Copy `site.yml.sample` to `site.yml`: + + +``` +`$ mv site.yml.sample site.yml` +``` + +Create `all.yml` in the `group_vars` directory: + + +``` +$ cat << EOF >> group_vars/all.yml +ceph_origin: repository +ceph_repository: community +ceph_repository_type: cdn +ceph_stable_release: nautilus +monitor_interface: wlan0 +public_network: "192.168.100.0/24" +cluster_network: "192.168.100.0/24" +dashboard_enabled: false +configure_firewall: false +EOF +``` + +Create `osds.yml` in the `group_vars` directory: + + +``` +$ cat << EOF >> group_vars/all.yml +osd_scenario: collocated +devices: + - /dev/sda +\- /dev/sdb +EOF +``` + +Create an inventory file: + + +``` +$ cat << EOF >> inventory +[mons] +rpi4b4-0 + +[osds] +rpi4b4-1 +rpi4b4-2 +rpi4b4-3 +EOF +``` + +As of this writing, there is a bug in the ceph-ansible repository (according to this [bug ticket][9]). You can mitigate the bug by editing line 85 and 86 of the roles: + + +``` +    - (wait_for_all_osds_up.stdout | from_json)["osdmap"]["num_osds"] | int > 0 +    - (wait_for_all_osds_up.stdout | from_json)["osdmap"]["num_osds"] == (wait_for_all_osds_up.stdout | from_json)["osdmap"]["num_up_osds"] +``` + +#### 4\. Deploy Ceph + +Run the Ansible playbook with your inventory file: + + +``` +`$ ansible-playbook -i inventory site.yml` +``` + +After 15–20 minutes, you should see this result: + +![Ceph deployment][10] + +(Aaron John Canlas, [CC BY-SA 4.0][6]) + +### Next steps + +Previously, I [manually deployed][11] an OpenStack cluster in another Raspberry Pi cluster. I hope to integrate it with this one. I'm also looking into deploying with [TripleO][12]. + +The possibilities for Raspberry Pi, Ansible, and OpenStack are endless. Get started with your own experiment, and let me know how it goes in the comments. + +-------------------------------------------------------------------------------- + +via: https://opensource.com/article/21/1/ceph-raspberry-pi + +作者：[AJ Canlas][a] +选题：[lujun9972][b] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: https://opensource.com/users/ajscanlas +[b]: https://github.com/lujun9972 +[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/raspberrypi_board_vector_red.png?itok=yaqYjYqI (Vector, generic Raspberry Pi board) +[2]: https://ceph.io/ +[3]: https://opensource.com/business/15/1/introduction-ceph-storage-openstack +[4]: https://docs.ceph.com/projects/ceph-ansible/en/latest/index.html# +[5]: https://opensource.com/sites/default/files/uploads/architecture_0_0.png (Project architecture) +[6]: https://creativecommons.org/licenses/by-sa/4.0/ +[7]: https://docs.ceph.com/en/latest/glossary/#term-Ceph-Monitor +[8]: https://docs.ceph.com/en/latest/glossary/#term-OSD +[9]: https://tracker.ceph.com/issues/43430 +[10]: https://opensource.com/sites/default/files/uploads/ceph.png (Ceph deployment) +[11]: https://opensource.com/article/20/12/openstack-raspberry-pi +[12]: https://wiki.openstack.org/wiki/TripleO