用 OpenStack Designate 構建一個 DNS 即服務（DNSaaS）

學習如何安裝和設定 Designate，這是一個 OpenStack 的多租戶 DNS 即服務（DNSaaS）。

Designate 是一個多租戶的 DNS 即服務，它包括一個用於域名和記錄管理的 REST API 和整合了 Neutron 的框架，並支援 Bind9。

DNSaaS 可以提供：

• 一個管理區域和記錄的乾淨利落的 REST API
• 自動生成記錄（整合 OpenStack）
• 支援多個授權名字伺服器
• 可以託管多個專案/組織

這篇文章解釋了如何在 CentOS 和 RHEL 上手動安裝和設定 Designate 的最新版本，但是同樣的設定也可以用在其它發行版上。

在 OpenStack 上安裝 Designate

在我的 GitHub 倉庫裡，我已經放了 Ansible 的 bind 和 Designate 角色的示範設定。

這個設定假定 bing 服務是安裝 OpenStack 控制器節點之外（即使你可以在本地安裝 bind）。

1、在 OpenStack 控制節點上安裝 Designate 和 bind 軟體包：

# yum install openstack-designate-* bind bind-utils -y

2、建立 Designate 資料庫和使用者：

MariaDB [(none)]> CREATE DATABASE designate CHARACTER SET utf8 COLLATE utf8_general_ci;       MariaDB [(none)]> GRANT ALL PRIVILEGES ON designate.* TO \'designate'@'localhost' IDENTIFIED BY 'rhlab123';MariaDB [(none)]> GRANT ALL PRIVILEGES ON designate.* TO 'designate'@'%' \IDENTIFIED BY 'rhlab123';

注意：bind 包必須安裝在控制節點之外才能使遠端名字服務控制Remote Name Daemon Control（RNDC）功能正常。

設定 bind（DNS 伺服器）

1、生成 RNDC 檔案：

rndc-confgen -a -k designate -c /etc/rndc.key -r /dev/urandomcat <<EOF> etcrndc.confinclude "/etc/rndc.key";options {  default-key "designate";  default-server {{ DNS_SERVER_IP }};  default-port 953;};EOF

2、將下列設定新增到 named.conf：

include "/etc/rndc.key"; controls {  inet {{ DNS_SERVER_IP }} allow { localhost;{{ CONTROLLER_SERVER_IP }}; } keys { "designate"; };};

在 option 節中，新增：

options {  ...  allow-new-zones yes;  request-ixfr no;  listen-on port 53 { any; };  recursion no;  allow-query { 127.0.0.1; {{ CONTROLLER_SERVER_IP }}; };};

新增正確的許可權：

chown named:named /etc/rndc.keychown named:named /etc/rndc.confchmod 600 /etc/rndc.keychown -v root:named /etc/named.confchmod g+w /var/named# systemctl restart named# setsebool named_write_master_zones 1

3、把 rndc.key 和 rndc.conf 推入 OpenStack 控制節點：

# scp -r /etc/rndc* {{ CONTROLLER_SERVER_IP }}:/etc/

建立 OpenStack Designate 服務和端點

輸入：

# openstack user create --domain default --password-prompt designate# openstack role add --project services --user designate admin# openstack service create --name designate --description "DNS" dns# openstack endpoint create --region RegionOne dns public http://{{ CONTROLLER_SERVER_IP }}:9001/# openstack endpoint create --region RegionOne dns internal http://{{ CONTROLLER_SERVER_IP }}:9001/  # openstack endpoint create --region RegionOne dns admin http://{{ CONTROLLER_SERVER_IP }}:9001/

設定 Designate 服務

1、編輯 /etc/designate/designate.conf：

在 [service:api] 節設定 auth_strategy：

[service:api]listen = 0.0.0.0:9001auth_strategy = keystoneapi_base_uri = http://{{ CONTROLLER_SERVER_IP }}:9001/enable_api_v2 = Trueenabled_extensions_v2 = quotas, reports

在 [keystone_authtoken] 節設定下列選項：

[keystone_authtoken]auth_type = passwordusername = designatepassword = rhlab123project_name = serviceproject_domain_name = Defaultuser_domain_name = Defaultwww_authenticate_uri = http://{{ CONTROLLER_SERVER_IP }}:5000/auth_url = http://{{ CONTROLLER_SERVER_IP }}:5000/ 

在 [service:worker] 節，啟用 worker 模型：

enabled = Truenotify = True

在 [storage:sqlalchemy] 節，設定資料庫存取：

[storage:sqlalchemy]connection = mysql+pymysql://designate:rhlab123@{{ CONTROLLER_SERVER_IP }}/designate

填充 Designate 資料庫：

# su -s /bin/sh -c "designate-manage database sync" designate

2、 建立 Designate 的 pools.yaml 檔案（包含 target 和 bind 細節）：

編輯 /etc/designate/pools.yaml：

- name: default  # The name is immutable. There will be no option to change the name after  # creation and the only way will to change it will be to delete it  # (and all zones associated with it) and recreate it.  description: Default Pool  attributes: {}  # List out the NS records for zones hosted within this pool  # This should be a record that is created outside of designate, that  # points to the public IP of the controller node.  ns_records:    - hostname: {{Controller_FQDN}}. # Thisis mDNS      priority: 1  # List out the nameservers for this pool. These are the actual BIND servers.  # We use these to verify changes have propagated to all nameservers.  nameservers:    - host: {{ DNS_SERVER_IP }}      port: 53  # List out the targets for this pool. For BIND there will be one  # entry for each BIND server, as we have to run rndc command on each server  targets:    - type: bind9      description: BIND9 Server 1      # List out the designate-mdns servers from which BIND servers should      # request zone transfers (AXFRs) from.      # This should be the IP of the controller node.      # If you have multiple controllers you can add multiple masters      # by running designate-mdns on them, and adding them here.      masters:        - host: {{ CONTROLLER_SERVER_IP }}          port: 5354      # BIND Configuration options      options:        host: {{ DNS_SERVER_IP }}        port: 53        rndc_host: {{ DNS_SERVER_IP }}        rndc_port: 953        rndc_key_file: /etc/rndc.key        rndc_config_file: /etc/rndc.conf

填充 Designate 池：

su -s /bin/sh -c "designate-manage pool update" designate

3、啟動 Designate 中心和 API 服務：

systemctl enable --now designate-central designate-api

4、驗證 Designate 服務執行：

# openstack dns service list+--------------+--------+-------+--------------+| service_name | status | stats | capabilities |+--------------+--------+-------+--------------+| central      | UP     | -     | -            || api          | UP     | -     | -            || mdns         | UP     | -     | -            || worker       | UP     | -     | -            || producer     | UP     | -     | -            |+--------------+--------+-------+--------------+

用外部 DNS 設定 OpenStack Neutron

1、為 Designate 服務設定 iptables：

# iptables -I INPUT -p tcp -m multiport --dports 9001 -m comment --comment "designate incoming" -j ACCEPT       # iptables -I INPUT -p tcp -m multiport --dports 5354 -m comment --comment "Designate mdns incoming" -j ACCEPT       # iptables -I INPUT -p tcp -m multiport --dports 53 -m comment --comment "bind incoming" -j ACCEPT        # iptables -I INPUT -p udp -m multiport --dports 53 -m comment --comment "bind/powerdns incoming" -j ACCEPT       # iptables -I INPUT -p tcp -m multiport --dports 953 -m comment --comment "rndc incoming - bind only" -j ACCEPT       # service iptables save; service iptables restart# setsebool named_write_master_zones 1

2、 編輯 /etc/neutron/neutron.conf 的 [default] 節：

external_dns_driver = designate

3、 在 /etc/neutron/neutron.conf 中新增 [designate] 節：

[designate]url = http://{{ CONTROLLER_SERVER_IP }}:9001/v2 ## This end point of designateauth_type = passwordauth_url = http://{{ CONTROLLER_SERVER_IP }}:5000username = designatepassword = rhlab123project_name = servicesproject_domain_name = Defaultuser_domain_name = Defaultallow_reverse_dns_lookup = Trueipv4_ptr_zone_prefix_size = 24ipv6_ptr_zone_prefix_size = 116 

4、編輯 neutron.conf 的 dns_domain：

dns_domain = rhlab.dev.

重新啟動：

# systemctl restart neutron-*

5、在 /etc/neutron/plugins/ml2/ml2_conf.ini 中的組成層 2（ML2）中新增 dns：

extension_drivers=port_security,qos,dns

6、在 Designate 中新增區域：

# openstack zone create –[email protected] rhlab.dev.

在 rhlab.dev 區域中新增記錄：

# openstack recordset create --record '192.168.1.230' --type A rhlab.dev. Test

Designate 現在就安裝和設定好了。