Install and configure a compute node¶

This section describes how to install and configure the Compute service on a compute node.

Note

This section assumes that you are following the instructions in this guide step-by-step to configure the first compute node. If you want to configure additional compute nodes, prepare them in a similar fashion. Each additional compute node requires a unique IP address.

Prerequisites¶

Before you install and configure Zun, you must have Docker and Kuryr-libnetwork installed properly in the compute node, and have Etcd installed properly in the controller node. Refer Get Docker for Docker installation and Kuryr libnetwork installation guide, Etcd installation guide

Install and configure components¶

Create zun user and necessary directories:

Create user:

# groupadd --system zun
# useradd --home-dir "/var/lib/zun" \
      --create-home \
      --system \
      --shell /bin/false \
      -g zun \
      zun

Create directories:

# mkdir -p /etc/zun
# chown zun:zun /etc/zun

Install the following dependencies:

For Ubuntu, run:
```
# apt-get install python-pip git
```
For CentOS, run:
```
# yum install python-pip git python-devel libffi-devel gcc openssl-devel
```
Note

python-pip package is not in CentOS base repositories, may need to install EPEL repository in order to have python-pip available.

Clone and install zun:

# cd /var/lib/zun
# git clone -b stable/train https://git.openstack.org/openstack/zun.git
# chown -R zun:zun zun
# cd zun
# pip install -r requirements.txt
# python setup.py install

Generate a sample configuration file:

# su -s /bin/sh -c "oslo-config-generator \
    --config-file etc/zun/zun-config-generator.conf" zun
# su -s /bin/sh -c "cp etc/zun/zun.conf.sample \
    /etc/zun/zun.conf" zun
# su -s /bin/sh -c "cp etc/zun/rootwrap.conf \
    /etc/zun/rootwrap.conf" zun
# su -s /bin/sh -c "mkdir -p /etc/zun/rootwrap.d" zun
# su -s /bin/sh -c "cp etc/zun/rootwrap.d/* \
    /etc/zun/rootwrap.d/" zun

Configure sudoers for zun users:

Note

CentOS install binary files into /usr/bin/, replace /usr/local/bin/ directory with the correct in the following command.
```
# echo "zun ALL=(root) NOPASSWD: /usr/local/bin/zun-rootwrap \
    /etc/zun/rootwrap.conf *" | sudo tee /etc/sudoers.d/zun-rootwrap
```

Edit the /etc/zun/zun.conf:

In the [DEFAULT] section, configure RabbitMQ message queue access:
```
[DEFAULT]
...
transport_url = rabbit://openstack:RABBIT_PASS@controller
```
Replace RABBIT_PASS with the password you chose for the openstack account in RabbitMQ.
In the [DEFAULT] section, configure the path that is used by Zun to store the states:
```
[DEFAULT]
...
state_path = /var/lib/zun
```
In the [database] section, configure database access:
```
[database]
...
connection = mysql+pymysql://zun:ZUN_DBPASS@controller/zun
```
Replace ZUN_DBPASS with the password you chose for the zun database.

In the [keystone_auth] section, configure Identity service access:

[keystone_auth]
memcached_servers = controller:11211
www_authenticate_uri = http://controller:5000
project_domain_name = default
project_name = service
user_domain_name = default
password = ZUN_PASS
username = zun
auth_url = http://controller:5000
auth_type = password
auth_version = v3
auth_protocol = http
service_token_roles_required = True
endpoint_type = internalURL

In the [keystone_authtoken] section, configure Identity service access:

[keystone_authtoken]
...
memcached_servers = controller:11211
www_authenticate_uri= http://controller:5000
project_domain_name = default
project_name = service
user_domain_name = default
password = ZUN_PASS
username = zun
auth_url = http://controller:5000
auth_type = password

Replace ZUN_PASS with the password you chose for the zun user in the Identity service.

In the [oslo_concurrency] section, configure the lock_path:

[oslo_concurrency]
...
lock_path = /var/lib/zun/tmp

(Optional) If you want to run both containers and nova instances in this compute node, in the [compute] section, configure the host_shared_with_nova:
```
[compute]
...
host_shared_with_nova = true
```

Note

Make sure that /etc/zun/zun.conf still have the correct permissions. You can set the permissions again with:

# chown zun:zun /etc/zun/zun.conf

Configure Docker and Kuryr:
- Create the directory /etc/systemd/system/docker.service.d
```
# mkdir -p /etc/systemd/system/docker.service.d
```
- Create the file /etc/systemd/system/docker.service.d/docker.conf. Configure docker to listen to port 2375 as well as the default unix socket. Also, configure docker to use etcd3 as storage backend:
```
[Service]
ExecStart=
ExecStart=/usr/bin/dockerd --group zun -H tcp://compute1:2375 -H unix:///var/run/docker.sock --cluster-store etcd://controller:2379
```
- Restart Docker:
```
# systemctl daemon-reload
# systemctl restart docker
```
- Edit the Kuryr config file /etc/kuryr/kuryr.conf. Set capability_scope to global and process_external_connectivity to False:
```
[DEFAULT]
...
capability_scope = global
process_external_connectivity = False
```
- Restart Kuryr-libnetwork:
```
# systemctl restart kuryr-libnetwork
```

Finalize installation¶

Create an upstart config, it could be named as /etc/systemd/system/zun-compute.service:

Note

CentOS install binary files into /usr/bin/, replace /usr/local/bin/ directory with the correct in the following example file.
```
[Unit]
Description = OpenStack Container Service Compute Agent

[Service]
ExecStart = /usr/local/bin/zun-compute
User = zun

[Install]
WantedBy = multi-user.target
```

Enable and start zun-compute:

# systemctl enable zun-compute
# systemctl start zun-compute

Verify that zun-compute services are running:
```
# systemctl status zun-compute
```