# Inventory > The main config file for Pigsty --- Each pigsty deployment has a corresponding config **inventory**. It could be stored in a local config file in YAML format, or dynamically generated from [CMDB](https://docs.ansible.com/ansible/2.9/user_guide/intro_dynamic_inventory.html) or any ansible compatible format. Pigsty uses one monolith YAML config file by default, which is [`pigsty.yml`](https://github.com/pgsty/pigsty/blob/v3.7.0/pigsty.yml), [located](https://github.com/pgsty/pigsty/blob/v3.7.0/ansible.cfg#L3) in the pigsty home directory. - **`pigsty/`** - [`pigsty.yml`](https://github.com/pgsty/pigsty/blob/v3.7.0/pigsty.yml) - [`ansible.cfg`](https://github.com/pgsty/pigsty/blob/v3.7.0/ansible.cfg) The [`configure`](/docs/config/configure) script will generate the `pigsty.yml` file scaffold with good defaults according to your env and input, but it's **OPTIONAL**: you can always edit the `pigsty.yml` file directly as the [**tutorial**](/docs/config/tutorial) shows. -------- ## Structure The inventory consists of two parts: **global vars** & multiple **groups**. You can define new clusters in `all.children`. And describe infra with global vars: `all.vars`. Which may look like this: ```yaml all: # Top-level object: all vars: {...} # Global Parameters children: # Group Definitions infra: # Group Definition: 'infra' hosts: {...} # Group Membership: 'infra' vars: {...} # Group Parameters: 'infra' etcd: {...} # Group Definition: 'etcd' pg-meta: {...} # Group Definition: 'pg-meta' pg-test: {...} # Group Definition: 'pg-test' redis-test: {...} # Group Definition: 'redis-test' # ... ``` There are plenty of examples under [`conf/`](https://github.com/pgsty/pigsty/blob/v3.7.0/conf/README.md), which can also be used as templates during `configure`. ------ ## Cluster Each ansible group may represent a cluster, which could be a Node cluster, PostgreSQL cluster, Redis cluster, Etcd cluster, or Minio cluster, etc… Cluster definition consists of two parts: **hosts** & **vars**. You can define cluster members in `.hosts` and describe cluster with parameters in `.vars`. Here's an example of a 3-node HA PG cluster: ```yaml all: children: # All Groups pg-test: # Group Name hosts: # Group Host (Cluster Membership) 10.10.10.11: { pg_seq: 1, pg_role: primary } # Host1 10.10.10.12: { pg_seq: 2, pg_role: replica } # Host2 10.10.10.13: { pg_seq: 3, pg_role: offline } # Host3 vars: # Group Vars (Cluster Parameters) pg_cluster: pg-test ``` The `vars` in cluster level will override the global vars, and `vars` in host level will override the cluster vars and global vars. ------ ## Parameter Parameters are key-value pairs that define all entities in the deployment. The key is a string name, and the value can be one of five types: boolean, string, number, array, or object. And parameters can be set at different levels with the following precedence: | Level | Location | Description | Precedence | |:------------|:---------------------------|:----------------------------------------------|:------------| | CLI Args | Command Line | via `-e` cli param arg | Highest (5) | | Host Vars | `.hosts.` | Parameters specific to a single host | High (4) | | Group Vars | `.vars` | Parameters shared by hosts in a group/cluster | Medium (3) | | Global Vars | `all.vars` | Parameters shared by all hosts | Low (2) | | Defaults | `/default/main.yml` | Role implementation default values | Lowest (1) | Here are some examples about parameter precedence: - Override the PostgreSQL major version with Playbook CLI Args `-e pg_version=16` - Override pg instance role with Instance Level Parameter `pg_role` on Host Vars - Override pg cluster name with Cluster Level Parameter `pg_cluster` on Group Vars. - Specify global NTP servers with Global Parameter `node_ntp_servers` on Global Vars - If no `pg_version` is set, pigsty will use the default value from role implementation (`18` by default) Every parameter has a proper default value except for mandatory **IDENTITY PARAMETERS**; they are used as identifiers and must be set explicitly. Such as [`pg_cluster`](/docs/pgsql/param#pg_cluster), [`pg_role`](/docs/pgsql/param#pg_role), and [`pg_seq`](/docs/pgsql/param#pg_seq) in above snippet. Available parameters vary according to the modules: | [PGSQL](/docs/pgsql/param) | [INFRA](/docs/infra/param) | [NODE](/docs/node/param) | [ETCD](/docs/etcd/param) | |:----------------------------------------------------------------------------:|:------------------------------------------------------------------------------:|:-------------------------------------------------------------------------------:|:-------------------------------------------------------------------------------:| | [MINIO](/docs/minio/param) | [REDIS](/docs/redis/param) | [DOCKER](/docs/docker/param) | [FERRET](/docs/ferret/param) | ------ ## Reference Pigsty has **290+** parameters, check module parameters for details. | Module | Section | Description | Count | |--------------------------------|----------------------------------------------------|-------------------------------------|-------| | [`INFRA`](/docs/infra/param) | [`META`](/docs/infra/param#meta) | Pigsty Metadata | 4 | | [`INFRA`](/docs/infra/param) | [`CA`](/docs/infra/param#ca) | Self-Signed CA | 3 | | [`INFRA`](/docs/infra/param) | [`INFRA_ID`](/docs/infra/param#infra_id) | Infra Portals & Identity | 2 | | [`INFRA`](/docs/infra/param) | [`REPO`](/docs/infra/param#repo) | Local Software Repo | 9 | | [`INFRA`](/docs/infra/param) | [`INFRA_PACKAGE`](/docs/infra/param#infra_package) | Infra Packages | 2 | | [`INFRA`](/docs/infra/param) | [`NGINX`](/docs/infra/param#nginx) | Nginx Web Server | 7 | | [`INFRA`](/docs/infra/param) | [`DNS`](/docs/infra/param#dns) | DNSMASQ Nameserver | 3 | | [`INFRA`](/docs/infra/param) | [`PROMETHEUS`](/docs/infra/param#prometheus) | Prometheus Stack | 18 | | [`INFRA`](/docs/infra/param) | [`GRAFANA`](/docs/infra/param#grafana) | Grafana Stack | 6 | | [`INFRA`](/docs/infra/param) | [`LOKI`](/docs/infra/param#loki) | Loki Logging Service | 4 | | [`NODE`](/docs/node/param) | [`NODE_ID`](/docs/node/param#node_id) | Node Identity Parameters | 5 | | [`NODE`](/docs/node/param) | [`NODE_DNS`](/docs/node/param#node_dns) | Node domain names & resolver | 6 | | [`NODE`](/docs/node/param) | [`NODE_PACKAGE`](/docs/node/param#node_package) | Node Repo & Packages | 5 | | [`NODE`](/docs/node/param) | [`NODE_TUNE`](/docs/node/param#node_tune) | Node Tuning & Kernel features | 10 | | [`NODE`](/docs/node/param) | [`NODE_ADMIN`](/docs/node/param#node_admin) | Admin User & Credentials | 7 | | [`NODE`](/docs/node/param) | [`NODE_TIME`](/docs/node/param#node_time) | Node Timezone, NTP, Crontabs | 5 | | [`NODE`](/docs/node/param) | [`NODE_VIP`](/docs/node/param#node_vip) | Node Keepalived L2 VIP | 8 | | [`NODE`](/docs/node/param) | [`HAPROXY`](/docs/node/param#haproxy) | HAProxy the load balancer | 10 | | [`NODE`](/docs/node/param) | [`NODE_EXPORTER`](/docs/node/param#node_exporter) | Node Monitoring Agent | 3 | | [`NODE`](/docs/node/param) | [`PROMTAIL`](/docs/node/param#promtail) | Promtail logging Agent | 4 | | [`DOCKER`](/docs/docker/param) | [`DOCKER`](/docs/docker/param) | Docker Daemon | 4 | | [`ETCD`](/docs/etcd/param) | [`ETCD`](/docs/etcd/param#etcd) | ETCD DCS Cluster | 10 | | [`MINIO`](/docs/minio/param) | [`MINIO`](/docs/minio/param#minio) | MINIO S3 Object Storage | 15 | | [`REDIS`](/docs/redis/param) | [`REDIS`](/docs/redis/param) | Redis the key-value NoSQL cache | 20 | | [`PGSQL`](/docs/pgsql/param) | [`PG_ID`](/docs/pgsql/param#pg_id) | PG Identity Parameters | 11 | | [`PGSQL`](/docs/pgsql/param) | [`PG_BUSINESS`](/docs/pgsql/param#pg_business) | PG Business Object Definition | 12 | | [`PGSQL`](/docs/pgsql/param) | [`PG_INSTALL`](/docs/pgsql/param#pg_install) | Install PG Packages & Extensions | 10 | | [`PGSQL`](/docs/pgsql/param) | [`PG_BOOTSTRAP`](/docs/pgsql/param#pg_bootstrap) | Init HA PG Cluster with Patroni | 35 | | [`PGSQL`](/docs/pgsql/param) | [`PG_PROVISION`](/docs/pgsql/param#pg_provision) | Create in-database objects | 9 | | [`PGSQL`](/docs/pgsql/param) | [`PG_BACKUP`](/docs/pgsql/param#pg_backup) | Set Backup Repo with pgBackRest | 5 | | [`PGSQL`](/docs/pgsql/param) | [`PG_ACCESS`](/docs/pgsql/param#pg_access) | Exposing service, bind vip, dns | 16 | | [`PGSQL`](/docs/pgsql/param) | [`PG_MONITOR`](/docs/pgsql/param#pg_monitor) | Collect metrics & logs for Postgres | 18 | | [`PGSQL`](/docs/pgsql/param) | [`PG_EXPORTER`](/docs/pgsql/param#pg_remove) | Remove a Postgres cluster | 4 |