部署生產級的 Kubernetes 集羣，使用kubespray

時間 2019-11-09

標籤部署生產 kubernetes 集羣使用 kubespray 欄目負載均衡简体版

原文原文鏈接

部署生產級的 Kubernetes 集羣，使用kubespray

項目源碼，https://github.com/openthings/kubespray
國內部署，https://github.com/zhangguanzhang/Kubernetes-ansible

歡迎加入 kubernetes slack, channel #kubespray. 得到邀請從這裏 herehtml

能夠部署到 AWS, GCE, Azure, OpenStack, vSphere, Oracle Cloud Infrastructure (Experimental), 或 Baremetal
Highly available cluster
Composable (Choice of the network plugin for instance)
Supports most popular Linux distributions
Continuous integration tests

快速開始

To deploy the cluster you can use :node

Ansible

# Install dependencies from ``requirements.txt``
sudo pip install -r requirements.txt

# Copy ``inventory/sample`` as ``inventory/mycluster``
cp -rfp inventory/sample/* inventory/mycluster

# Update Ansible inventory file with inventory builder
declare -a IPS=(10.10.1.3 10.10.1.4 10.10.1.5)
CONFIG_FILE=inventory/mycluster/hosts.ini python3 contrib/inventory_builder/inventory.py ${IPS[@]}

# Review and change parameters under ``inventory/mycluster/group_vars``
cat inventory/mycluster/group_vars/all.yml
cat inventory/mycluster/group_vars/k8s-cluster.yml

# Deploy Kubespray with Ansible Playbook
ansible-playbook -i inventory/mycluster/hosts.ini cluster.yml

Note: When Ansible is already installed via system packages on the control machine, other python packages installed via sudo pip install -r requirements.txt will go to a different directory tree (e.g. /usr/local/lib/python2.7/dist-packages on Ubuntu) from Ansible's (e.g. /usr/lib/python2.7/dist-packages/ansible still on Ubuntu). As a consequence, ansible-playbook command will fail with:python

ERROR! no action detected in task. This often indicates a misspelled module name, or incorrect module path.

probably pointing on a task depending on a module present in requirements.txt (i.e. "unseal vault").nginx

One way of solving this would be to uninstall the Ansible package and then, to install it via pip but it is not always possible. A workaround consists of setting ANSIBLE_LIBRARY and ANSIBLE_MODULE_UTILS environment variables respectively to the ansible/modules and ansible/module_utils subdirectories of pip packages installation location, which can be found in the Location field of the output of pip show [package] before executing ansible-playbook.git

Vagrant

For Vagrant we need to install python dependencies for provisioning tasks. Check if Python and pip are installed:github

python -V && pip -V

If this returns the version of the software, you're good to go. If not, download and install Python from here https://www.python.org/downloads/source/ Install the necessary requirementsdocker

sudo pip install -r requirements.txt
vagrant up

Documents

Supported Linux Distributions

Container Linux by CoreOS
Debian Jessie, Stretch, Wheezy
Ubuntu 16.04, 18.04
CentOS/RHEL 7
Fedora 28
Fedora/CentOS Atomic
openSUSE Leap 42.3/Tumbleweed

Note: Upstart/SysV init based OS types are not supported.bootstrap

Supported Components

Core
- kubernetes v1.11.3
- etcd v3.2.18
- docker v17.03 (see note)
- rkt v1.21.0 (see Note 2)
Network Plugin
- calico v3.1.3
- canal (given calico/flannel versions)
- cilium v1.2.0
- contiv v1.1.7
- flanneld v0.10.0
- weave v2.4.1
Application
- cephfs-provisioner v2.1.0-k8s1.11
- cert-manager v0.5.0
- coredns v1.2.2
- ingress-nginx v0.19.0

Note: kubernetes doesn't support newer docker versions ("Version 17.03 is recommended... Versions 17.06+ might work, but have not yet been tested and verified by the Kubernetes node team" cf. Bootstrapping Clusters with kubeadm). Among other things kubelet currently breaks on docker's non-standard version numbering (it no longer uses semantic versioning). To ensure auto-updates don't break your cluster look into e.g. yum versionlock plugin or apt pin).app

Note 2: rkt support as docker alternative is limited to control plane (etcd and kubelet). Docker is still used for Kubernetes cluster workloads and network plugins' related OS services. Also note, only one of the supported network plugins can be deployed for a given single cluster.python2.7

Requirements

Ansible v2.4 (or newer) and python-netaddr is installed on the machine that will run Ansible commands
Jinja 2.9 (or newer) is required to run the Ansible Playbooks
The target servers must have access to the Internet in order to pull docker images.
The target servers are configured to allow IPv4 forwarding.
Your ssh key must be copied to all the servers part of your inventory.
The firewalls are not managed, you'll need to implement your own rules the way you used to. in order to avoid any issue during deployment you should disable your firewall.
If kubespray is ran from non-root user account, correct privilege escalation method should be configured in the target servers. Then the ansible_become flag or command parameters --become or -b should be specified.

Network Plugins

You can choose between 6 network plugins. (default: calico, except Vagrant uses flannel)

flannel: gre/vxlan (layer 2) networking.
calico: bgp (layer 3) networking.
canal: a composition of calico and flannel plugins.
cilium: layer 3/4 networking (as well as layer 7 to protect and secure application protocols), supports dynamic insertion of BPF bytecode into the Linux kernel to implement security services, networking and visibility logic.
contiv: supports vlan, vxlan, bgp and Cisco SDN networking. This plugin is able to apply firewall policies, segregate containers in multiple network and bridging pods onto physical networks.
weave: Weave is a lightweight container overlay network that doesn't require an external K/V database cluster. (Please refer to weave troubleshooting documentation).

The choice is defined with the variable kube_network_plugin. There is also an option to leverage built-in cloud provider networking instead. See also Network checker.