Infra as Code

Pigsty uses Infrastructure as Code (IaC) philosophy to manage all components, providing declarative management for large-scale clusters.

Pigsty follows the IaC and GitOPS philosophy: use a declarative config inventory to describe the entire environment, and materialize it through idempotent playbooks.

Users describe their desired state declaratively through parameters, and playbooks idempotently adjust target nodes to reach that state. This is similar to Kubernetes CRDs & Operators, but Pigsty implements this functionality on bare metal and virtual machines through Ansible.

Pigsty was born to solve the operational management problem of ultra-large-scale PostgreSQL clusters. The idea behind it is simple — we need the ability to replicate the entire infrastructure (100+ database clusters + PG/Redis + observability) on ready servers within ten minutes. No GUI + ClickOps can complete such a complex task in such a short time, making CLI + IaC the only choice — it provides precise, efficient control.

The config inventory pigsty.yml file describes the state of the entire deployment. Whether it’s production (prod), staging, test, or development (devbox) environments, the difference between infrastructures lies only in the config inventory, while the deployment delivery logic is exactly the same.

You can use git for version control and auditing of this deployment “seed/gene”, and Pigsty even supports storing the config inventory as database tables in PostgreSQL CMDB, further achieving Infra as Data capability. Seamlessly integrate with your existing workflows.

IaC is designed for professional users and enterprise scenarios but is also deeply optimized for individual developers and SMBs. Even if you’re not a professional DBA, you don’t need to understand these hundreds of adjustment knobs and switches. All parameters come with well-performing default values. You can get an out-of-the-box single-node database with zero configuration; Simply add two more IP addresses to get an enterprise-grade high-availability PostgreSQL cluster.


Declare Modules

Take the following default config snippet as an example. This config describes a node 10.10.10.10 with INFRA, NODE, ETCD, and PGSQL modules installed.

# monitoring, alerting, DNS, NTP and other infrastructure cluster...
infra: { hosts: { 10.10.10.10: { infra_seq: 1 } } }

# minio cluster, s3 compatible object storage
minio: { hosts: { 10.10.10.10: { minio_seq: 1 } }, vars: { minio_cluster: minio } }

# etcd cluster, used as DCS for PostgreSQL high availability
etcd: { hosts: { 10.10.10.10: { etcd_seq: 1 } }, vars: { etcd_cluster: etcd } }

# PGSQL example cluster: pg-meta
pg-meta: { hosts: { 10.10.10.10: { pg_seq: 1, pg_role: primary }, vars: { pg_cluster: pg-meta } }

To actually install these modules, execute the following playbooks:

./infra.yml -l 10.10.10.10  # Initialize infra module on node 10.10.10.10
./etcd.yml  -l 10.10.10.10  # Initialize etcd module on node 10.10.10.10
./minio.yml -l 10.10.10.10  # Initialize minio module on node 10.10.10.10
./pgsql.yml -l 10.10.10.10  # Initialize pgsql module on node 10.10.10.10

Declare Clusters

You can declare PostgreSQL database clusters by installing the PGSQL module on multiple nodes, making them a service unit:

For example, to deploy a three-node high-availability PostgreSQL cluster using streaming replication on the following three Pigsty-managed nodes, you can add the following definition to the all.children section of the config file pigsty.yml:

pg-test:
  hosts:
    10.10.10.11: { pg_seq: 1, pg_role: primary }
    10.10.10.12: { pg_seq: 2, pg_role: replica }
    10.10.10.13: { pg_seq: 3, pg_role: offline }
  vars:  { pg_cluster: pg-test }

After defining, you can use playbooks to create the cluster:

bin/pgsql-add pg-test   # Create the pg-test cluster

pigsty-iac.jpg

You can use different instance roles such as primary, replica, offline, delayed, sync standby; as well as different clusters: such as standby clusters, Citus clusters, and even Redis / MinIO / Etcd clusters


Customize Cluster Content

Not only can you define clusters declaratively, but you can also define databases, users, services, and HBA rules within the cluster. For example, the following config file deeply customizes the content of the default pg-meta single-node database cluster:

Including: declaring six business databases and seven business users, adding an extra standby service (synchronous standby, providing read capability with no replication delay), defining some additional pg_hba rules, an L2 VIP address pointing to the cluster primary, and a customized backup strategy.

pg-meta:
  hosts: { 10.10.10.10: { pg_seq: 1, pg_role: primary , pg_offline_query: true } }
  vars:
    pg_cluster: pg-meta
    pg_databases:                       # define business databases on this cluster, array of database definition
      - name: meta                      # REQUIRED, `name` is the only mandatory field of a database definition
        baseline: cmdb.sql              # optional, database sql baseline path, (relative path among ansible search path, e.g files/)
        pgbouncer: true                 # optional, add this database to pgbouncer database list? true by default
        schemas: [pigsty]               # optional, additional schemas to be created, array of schema names
        extensions:                     # optional, additional extensions to be installed: array of `{name[,schema]}`
          - { name: postgis , schema: public }
          - { name: timescaledb }
        comment: pigsty meta database   # optional, comment string for this database
        owner: postgres                # optional, database owner, postgres by default
        template: template1            # optional, which template to use, template1 by default
        encoding: UTF8                 # optional, database encoding, UTF8 by default. (MUST same as template database)
        locale: C                      # optional, database locale, C by default.  (MUST same as template database)
        lc_collate: C                  # optional, database collate, C by default. (MUST same as template database)
        lc_ctype: C                    # optional, database ctype, C by default.   (MUST same as template database)
        tablespace: pg_default         # optional, default tablespace, 'pg_default' by default.
        allowconn: true                # optional, allow connection, true by default. false will disable connect at all
        revokeconn: false              # optional, revoke public connection privilege. false by default. (leave connect with grant option to owner)
        register_datasource: true      # optional, register this database to grafana datasources? true by default
        connlimit: -1                  # optional, database connection limit, default -1 disable limit
        pool_auth_user: dbuser_meta    # optional, all connection to this pgbouncer database will be authenticated by this user
        pool_mode: transaction         # optional, pgbouncer pool mode at database level, default transaction
        pool_size: 64                  # optional, pgbouncer pool size at database level, default 64
        pool_size_reserve: 32          # optional, pgbouncer pool size reserve at database level, default 32
        pool_size_min: 0               # optional, pgbouncer pool size min at database level, default 0
        pool_max_db_conn: 100          # optional, max database connections at database level, default 100
      - { name: grafana  ,owner: dbuser_grafana  ,revokeconn: true ,comment: grafana primary database }
      - { name: bytebase ,owner: dbuser_bytebase ,revokeconn: true ,comment: bytebase primary database }
      - { name: kong     ,owner: dbuser_kong     ,revokeconn: true ,comment: kong the api gateway database }
      - { name: gitea    ,owner: dbuser_gitea    ,revokeconn: true ,comment: gitea meta database }
      - { name: wiki     ,owner: dbuser_wiki     ,revokeconn: true ,comment: wiki meta database }
    pg_users:                           # define business users/roles on this cluster, array of user definition
      - name: dbuser_meta               # REQUIRED, `name` is the only mandatory field of a user definition
        password: DBUser.Meta           # optional, password, can be a scram-sha-256 hash string or plain text
        login: true                     # optional, can log in, true by default  (new biz ROLE should be false)
        superuser: false                # optional, is superuser? false by default
        createdb: false                 # optional, can create database? false by default
        createrole: false               # optional, can create role? false by default
        inherit: true                   # optional, can this role use inherited privileges? true by default
        replication: false              # optional, can this role do replication? false by default
        bypassrls: false                # optional, can this role bypass row level security? false by default
        pgbouncer: true                 # optional, add this user to pgbouncer user-list? false by default (production user should be true explicitly)
        connlimit: -1                   # optional, user connection limit, default -1 disable limit
        expire_in: 3650                 # optional, now + n days when this role is expired (OVERWRITE expire_at)
        expire_at: '2030-12-31'         # optional, YYYY-MM-DD 'timestamp' when this role is expired  (OVERWRITTEN by expire_in)
        comment: pigsty admin user      # optional, comment string for this user/role
        roles: [dbrole_admin]           # optional, belonged roles. default roles are: dbrole_{admin,readonly,readwrite,offline}
        parameters: {}                  # optional, role level parameters with `ALTER ROLE SET`
        pool_mode: transaction          # optional, pgbouncer pool mode at user level, transaction by default
        pool_connlimit: -1              # optional, max database connections at user level, default -1 disable limit
      - {name: dbuser_view     ,password: DBUser.Viewer   ,pgbouncer: true ,roles: [dbrole_readonly], comment: read-only viewer for meta database}
      - {name: dbuser_grafana  ,password: DBUser.Grafana  ,pgbouncer: true ,roles: [dbrole_admin]    ,comment: admin user for grafana database   }
      - {name: dbuser_bytebase ,password: DBUser.Bytebase ,pgbouncer: true ,roles: [dbrole_admin]    ,comment: admin user for bytebase database  }
      - {name: dbuser_kong     ,password: DBUser.Kong     ,pgbouncer: true ,roles: [dbrole_admin]    ,comment: admin user for kong api gateway   }
      - {name: dbuser_gitea    ,password: DBUser.Gitea    ,pgbouncer: true ,roles: [dbrole_admin]    ,comment: admin user for gitea service      }
      - {name: dbuser_wiki     ,password: DBUser.Wiki     ,pgbouncer: true ,roles: [dbrole_admin]    ,comment: admin user for wiki.js service    }
    pg_services:                        # extra services in addition to pg_default_services, array of service definition
      # standby service will route {ip|name}:5435 to sync replica's pgbouncer (5435->6432 standby)
      - name: standby                   # required, service name, the actual svc name will be prefixed with `pg_cluster`, e.g: pg-meta-standby
        port: 5435                      # required, service exposed port (work as kubernetes service node port mode)
        ip: "*"                         # optional, service bind ip address, `*` for all ip by default
        selector: "[]"                  # required, service member selector, use JMESPath to filter inventory
        dest: default                   # optional, destination port, default|postgres|pgbouncer|<port_number>, 'default' by default
        check: /sync                    # optional, health check url path, / by default
        backup: "[? pg_role == `primary`]"  # backup server selector
        maxconn: 3000                   # optional, max allowed front-end connection
        balance: roundrobin             # optional, haproxy load balance algorithm (roundrobin by default, other: leastconn)
        options: 'inter 3s fastinter 1s downinter 5s rise 3 fall 3 on-marked-down shutdown-sessions slowstart 30s maxconn 3000 maxqueue 128 weight 100'
    pg_hba_rules:
      - {user: dbuser_view , db: all ,addr: infra ,auth: pwd ,title: 'allow grafana dashboard access cmdb from infra nodes'}
    pg_vip_enabled: true
    pg_vip_address: 10.10.10.2/24
    pg_vip_interface: eth1
    node_crontab:  # make a full backup 1 am everyday
      - '00 01 * * * postgres /pg/bin/pg-backup full'

Declare Access Control

You can also deeply customize Pigsty’s access control capabilities through declarative configuration. For example, the following config file provides deep security customization for the pg-meta cluster:

Uses the three-node core cluster template: crit.yml, to ensure data consistency is prioritized with zero data loss during failover. Enables L2 VIP and restricts database and connection pool listening addresses to local loopback IP + internal network IP + VIP three specific addresses. The template enforces Patroni’s SSL API and Pgbouncer’s SSL, and in HBA rules, enforces SSL usage for accessing the database cluster. Also enables the $libdir/passwordcheck extension in pg_libs to enforce password strength security policy.

Finally, a separate pg-meta-delay cluster is declared as pg-meta’s delayed replica from one hour ago, for emergency data deletion recovery.

pg-meta:      # 3 instance postgres cluster `pg-meta`
  hosts:
    10.10.10.10: { pg_seq: 1, pg_role: primary }
    10.10.10.11: { pg_seq: 2, pg_role: replica }
    10.10.10.12: { pg_seq: 3, pg_role: replica , pg_offline_query: true }
  vars:
    pg_cluster: pg-meta
    pg_conf: crit.yml
    pg_users:
      - { name: dbuser_meta , password: DBUser.Meta   , pgbouncer: true , roles: [ dbrole_admin ] , comment: pigsty admin user }
      - { name: dbuser_view , password: DBUser.Viewer , pgbouncer: true , roles: [ dbrole_readonly ] , comment: read-only viewer for meta database }
    pg_databases:
      - {name: meta ,baseline: cmdb.sql ,comment: pigsty meta database ,schemas: [pigsty] ,extensions: [{name: postgis, schema: public}, {name: timescaledb}]}
    pg_default_service_dest: postgres
    pg_services:
      - { name: standby ,src_ip: "*" ,port: 5435 , dest: default ,selector: "[]" , backup: "[? pg_role == `primary`]" }
    pg_vip_enabled: true
    pg_vip_address: 10.10.10.2/24
    pg_vip_interface: eth1
    pg_listen: '${ip},${vip},${lo}'
    patroni_ssl_enabled: true
    pgbouncer_sslmode: require
    pgbackrest_method: minio
    pg_libs: 'timescaledb, $libdir/passwordcheck, pg_stat_statements, auto_explain' # add passwordcheck extension to enforce strong password
    pg_default_roles:                 # default roles and users in postgres cluster
      - { name: dbrole_readonly  ,login: false ,comment: role for global read-only access     }
      - { name: dbrole_offline   ,login: false ,comment: role for restricted read-only access }
      - { name: dbrole_readwrite ,login: false ,roles: [dbrole_readonly]               ,comment: role for global read-write access }
      - { name: dbrole_admin     ,login: false ,roles: [pg_monitor, dbrole_readwrite]  ,comment: role for object creation }
      - { name: postgres     ,superuser: true  ,expire_in: 7300                        ,comment: system superuser }
      - { name: replicator ,replication: true  ,expire_in: 7300 ,roles: [pg_monitor, dbrole_readonly]   ,comment: system replicator }
      - { name: dbuser_dba   ,superuser: true  ,expire_in: 7300 ,roles: [dbrole_admin]  ,pgbouncer: true ,pool_mode: session, pool_connlimit: 16 , comment: pgsql admin user }
      - { name: dbuser_monitor ,roles: [pg_monitor] ,expire_in: 7300 ,pgbouncer: true ,parameters: {log_min_duration_statement: 1000 } ,pool_mode: session ,pool_connlimit: 8 ,comment: pgsql monitor user }
    pg_default_hba_rules:             # postgres host-based auth rules by default
      - {user: '${dbsu}'    ,db: all         ,addr: local     ,auth: ident ,title: 'dbsu access via local os user ident'  }
      - {user: '${dbsu}'    ,db: replication ,addr: local     ,auth: ident ,title: 'dbsu replication from local os ident' }
      - {user: '${repl}'    ,db: replication ,addr: localhost ,auth: ssl   ,title: 'replicator replication from localhost'}
      - {user: '${repl}'    ,db: replication ,addr: intra     ,auth: ssl   ,title: 'replicator replication from intranet' }
      - {user: '${repl}'    ,db: postgres    ,addr: intra     ,auth: ssl   ,title: 'replicator postgres db from intranet' }
      - {user: '${monitor}' ,db: all         ,addr: localhost ,auth: pwd   ,title: 'monitor from localhost with password' }
      - {user: '${monitor}' ,db: all         ,addr: infra     ,auth: ssl   ,title: 'monitor from infra host with password'}
      - {user: '${admin}'   ,db: all         ,addr: infra     ,auth: ssl   ,title: 'admin @ infra nodes with pwd & ssl'   }
      - {user: '${admin}'   ,db: all         ,addr: world     ,auth: cert  ,title: 'admin @ everywhere with ssl & cert'   }
      - {user: '+dbrole_readonly',db: all    ,addr: localhost ,auth: ssl   ,title: 'pgbouncer read/write via local socket'}
      - {user: '+dbrole_readonly',db: all    ,addr: intra     ,auth: ssl   ,title: 'read/write biz user via password'     }
      - {user: '+dbrole_offline' ,db: all    ,addr: intra     ,auth: ssl   ,title: 'allow etl offline tasks from intranet'}
    pgb_default_hba_rules:            # pgbouncer host-based authentication rules
      - {user: '${dbsu}'    ,db: pgbouncer   ,addr: local     ,auth: peer  ,title: 'dbsu local admin access with os ident'}
      - {user: 'all'        ,db: all         ,addr: localhost ,auth: pwd   ,title: 'allow all user local access with pwd' }
      - {user: '${monitor}' ,db: pgbouncer   ,addr: intra     ,auth: ssl   ,title: 'monitor access via intranet with pwd' }
      - {user: '${monitor}' ,db: all         ,addr: world     ,auth: deny  ,title: 'reject all other monitor access addr' }
      - {user: '${admin}'   ,db: all         ,addr: intra     ,auth: ssl   ,title: 'admin access via intranet with pwd'   }
      - {user: '${admin}'   ,db: all         ,addr: world     ,auth: deny  ,title: 'reject all other admin access addr'   }
      - {user: 'all'        ,db: all         ,addr: intra     ,auth: ssl   ,title: 'allow all user intra access with pwd' }

# OPTIONAL delayed cluster for pg-meta
pg-meta-delay:                    # delayed instance for pg-meta (1 hour ago)
  hosts: { 10.10.10.13: { pg_seq: 1, pg_role: primary, pg_upstream: 10.10.10.10, pg_delay: 1h } }
  vars: { pg_cluster: pg-meta-delay }

Citus Distributed Cluster

Below is a declarative configuration for a four-node Citus distributed cluster:

all:
  children:
    pg-citus0: # citus coordinator, pg_group = 0
      hosts: { 10.10.10.10: { pg_seq: 1, pg_role: primary } }
      vars: { pg_cluster: pg-citus0 , pg_group: 0 }
    pg-citus1: # citus data node 1
      hosts: { 10.10.10.11: { pg_seq: 1, pg_role: primary } }
      vars: { pg_cluster: pg-citus1 , pg_group: 1 }
    pg-citus2: # citus data node 2
      hosts: { 10.10.10.12: { pg_seq: 1, pg_role: primary } }
      vars: { pg_cluster: pg-citus2 , pg_group: 2 }
    pg-citus3: # citus data node 3, with an extra replica
      hosts:
        10.10.10.13: { pg_seq: 1, pg_role: primary }
        10.10.10.14: { pg_seq: 2, pg_role: replica }
      vars: { pg_cluster: pg-citus3 , pg_group: 3 }
  vars:                               # global parameters for all citus clusters
    pg_mode: citus                    # pgsql cluster mode: citus
    pg_shard: pg-citus                # citus shard name: pg-citus
    patroni_citus_db: meta            # citus distributed database name
    pg_dbsu_password: DBUser.Postgres # all dbsu password access for citus cluster
    pg_users: [ { name: dbuser_meta ,password: DBUser.Meta ,pgbouncer: true ,roles: [ dbrole_admin ] } ]
    pg_databases: [ { name: meta ,extensions: [ { name: citus }, { name: postgis }, { name: timescaledb } ] } ]
    pg_hba_rules:
      - { user: 'all' ,db: all  ,addr: 127.0.0.1/32 ,auth: ssl ,title: 'all user ssl access from localhost' }
      - { user: 'all' ,db: all  ,addr: intra        ,auth: ssl ,title: 'all user ssl access from intranet'  }

Redis Clusters

Below are declarative configuration examples for Redis primary-replica cluster, sentinel cluster, and Redis Cluster:

redis-ms: # redis classic primary & replica
  hosts: { 10.10.10.10: { redis_node: 1 , redis_instances: { 6379: { }, 6380: { replica_of: '10.10.10.10 6379' } } } }
  vars: { redis_cluster: redis-ms ,redis_password: 'redis.ms' ,redis_max_memory: 64MB }

redis-meta: # redis sentinel x 3
  hosts: { 10.10.10.11: { redis_node: 1 , redis_instances: { 26379: { } ,26380: { } ,26381: { } } } }
  vars:
    redis_cluster: redis-meta
    redis_password: 'redis.meta'
    redis_mode: sentinel
    redis_max_memory: 16MB
    redis_sentinel_monitor: # primary list for redis sentinel, use cls as name, primary ip:port
      - { name: redis-ms, host: 10.10.10.10, port: 6379 ,password: redis.ms, quorum: 2 }

redis-test: # redis native cluster: 3m x 3s
  hosts:
    10.10.10.12: { redis_node: 1 ,redis_instances: { 6379: { } ,6380: { } ,6381: { } } }
    10.10.10.13: { redis_node: 2 ,redis_instances: { 6379: { } ,6380: { } ,6381: { } } }
  vars: { redis_cluster: redis-test ,redis_password: 'redis.test' ,redis_mode: cluster, redis_max_memory: 32MB }

ETCD Cluster

Below is a declarative configuration example for a three-node Etcd cluster:

etcd: # dcs service for postgres/patroni ha consensus
  hosts:  # 1 node for testing, 3 or 5 for production
    10.10.10.10: { etcd_seq: 1 }  # etcd_seq required
    10.10.10.11: { etcd_seq: 2 }  # assign from 1 ~ n
    10.10.10.12: { etcd_seq: 3 }  # odd number please
  vars: # cluster level parameter override roles/etcd
    etcd_cluster: etcd  # mark etcd cluster name etcd
    etcd_safeguard: false # safeguard against purging
    etcd_clean: true # purge etcd during init process

MinIO Cluster

Below is a declarative configuration example for a three-node MinIO cluster:

minio:
  hosts:
    10.10.10.10: { minio_seq: 1 }
    10.10.10.11: { minio_seq: 2 }
    10.10.10.12: { minio_seq: 3 }
  vars:
    minio_cluster: minio
    minio_data: '/data{1...2}'          # use two disks per node
    minio_node: '${minio_cluster}-${minio_seq}.pigsty' # node name pattern
    haproxy_services:
      - name: minio                     # [required] service name, must be unique
        port: 9002                      # [required] service port, must be unique
        options:
          - option httpchk
          - option http-keep-alive
          - http-check send meth OPTIONS uri /minio/health/live
          - http-check expect status 200
        servers:
          - { name: minio-1 ,ip: 10.10.10.10 , port: 9000 , options: 'check-ssl ca-file /etc/pki/ca.crt check port 9000' }
          - { name: minio-2 ,ip: 10.10.10.11 , port: 9000 , options: 'check-ssl ca-file /etc/pki/ca.crt check port 9000' }
          - { name: minio-3 ,ip: 10.10.10.12 , port: 9000 , options: 'check-ssl ca-file /etc/pki/ca.crt check port 9000' }

Inventory

Describe your infrastructure and clusters using declarative configuration files

Configure

Use the configure script to automatically generate recommended configuration files based on your environment.

Parameters

Fine-tune Pigsty customization using configuration parameters

Conf Templates

Use pre-made configuration templates to quickly generate configuration files adapted to your environment

Use CMDB as Config Inventory

Use PostgreSQL as a CMDB metabase to store Ansible inventory.