Azure Database for PostgreSQL Terraform Module

Azure Database for PostgreSQL Single Server is a fully managed database service with minimal requirements for customizations of database. The single server platform is designed to handle most of the database management functions such as patching, backups, high availability, security with minimal user configuration and control. The architecture is optimized for built-in high availability with 99.99% availability on single availability zone. It supports community version of PostgreSQL 9.5, 9,6, 10, and 11.

Resources supported

• PostgreSQL Server
• PostgreSQL Database
• PostgreSQL Configuration
• PostgreSQL Firewall Rules
• PostgreSQL Active Directory Administrator
• PostgreSQL Customer Managed Key
• PostgreSQL Virtual Network Rule
• PostgreSQL Diagnostics
• Private Endpoints
• Private DNS zone for privatelink A records

module "postgresql-db" {
  source  = "kumarvna/postgresql-db/azurerm"
  version = "1.1.0"

  # By default, this module will create a resource group
  # proivde a name to use an existing resource group and set the argument 
  # to `create_resource_group = false` if you want to existing resoruce group. 
  # If you use existing resrouce group location will be the same as existing RG.
  create_resource_group = false
  resource_group_name   = "rg-shared-westeurope-01"
  location              = "westeurope"

  # PostgreSQL Server and Database settings
  postgresql_server_name = "mypostgresdbsrv01"

  postgresql_server_settings = {
    sku_name   = "GP_Gen5_8"
    storage_mb = 640000
    version    = "9.6"
    # default admin user `postgresadmin` and can be specified as per the choice here
    # by default random password created by this module. required password can be specified here
    admin_username = "postgresadmin"
    admin_password = "H@Sh1CoR3!"
    # Database name, charset and collection arguments  
    database_name = "demo-postgres-db"
    charset       = "UTF8"
    collation     = "English_United States.1252"
    # Storage Profile and other optional arguments
    auto_grow_enabled                = true
    backup_retention_days            = 7
    geo_redundant_backup_enabled     = true
    public_network_access_enabled    = true
    ssl_enforcement_enabled          = true
    ssl_minimal_tls_version_enforced = "TLS1_2"
  }

  # PostgreSQL Server Parameters 
  # For more information: https://bit.ly/3dbYTtB
  postgresql_configuration = {
    backslash_quote = "on"
  }

  # Use Virtual Network service endpoints and rules for Azure Database for PostgreSQL
  subnet_id = var.subnet_id

  # The URL to a Key Vault custom managed key
  key_vault_key_id = var.key_vault_key_id

  # To enable Azure Defender for database set `enable_threat_detection_policy` to true 
  enable_threat_detection_policy = true
  log_retention_days             = 30
  email_addresses_for_alerts     = ["user@example.com", "firstname.lastname@example.com"]

  # AD administrator for an Azure database for PostgreSQL
  # Allows you to set a user or group as the AD administrator for PostgreSQL server
  ad_admin_login_name = "firstname.lastname@example.com"

  # (Optional) To enable Azure Monitoring for Azure PostgreSQL database
  # (Optional) Specify `storage_account_name` to save monitoring logs to storage. 
  log_analytics_workspace_name = "loganalytics-we-sharedtest2"

  # Creating Private Endpoint requires, VNet name and address prefix to create a subnet
  # By default this will create a `privatelink.mysql.database.azure.com` DNS zone. 
  # To use existing private DNS zone specify `existing_private_dns_zone` with valid zone name
  enable_private_endpoint       = true
  virtual_network_name          = "vnet-shared-hub-westeurope-001"
  private_subnet_address_prefix = ["10.1.5.0/29"]
  #  existing_private_dns_zone     = "demo.example.com"

  # Firewall Rules to allow azure and external clients and specific Ip address/ranges. 
  firewall_rules = {
    access-to-azure = {
      start_ip_address = "0.0.0.0"
      end_ip_address   = "0.0.0.0"
    },
    desktop-ip = {
      start_ip_address = "49.204.228.223"
      end_ip_address   = "49.204.228.223"
    }
  }

  # Tags for Azure Resources
  tags = {
    Terraform   = "true"
    Environment = "dev"
    Owner       = "test-user"
  }
}

Default Local Administrator and the Password

This module utilizes postgresadmin as a local administrator on PostgreSQL server. If you want to you use custom username, then specify the same by setting up the argument admin_username with a valid user string.

By default, this module generates a strong password for PostgreSQL server also allows you to change the length of the random password (currently 24) using the random_password_length variable. If you want to set the custom password, specify the argument admin_password with a valid string.

postgresql_server_settings - Setting up your PostgreSQL Server

This object helps you setup desired PostgreSQL server and support following arguments.

Argument	Description
sku_name	Specifies the SKU Name for this PostgreSQL Server. The name of the SKU, follows the tier + family + cores pattern (e.g. B_Gen4_1, GP_Gen5_8). Valid values are B_Gen4_1, B_Gen4_2, B_Gen5_1, B_Gen5_2, GP_Gen4_2, GP_Gen4_4, GP_Gen4_8, GP_Gen4_16, GP_Gen4_32, GP_Gen5_2, GP_Gen5_4, GP_Gen5_8, GP_Gen5_16, GP_Gen5_32, GP_Gen5_64, MO_Gen5_2, MO_Gen5_4, MO_Gen5_8, MO_Gen5_16, MO_Gen5_32.
storage_mb	Max storage allowed for a server. Possible values are between 5120 MB(5GB) and 1048576 MB(1TB) for the Basic SKU and between 5120 MB(5GB) and 16777216 MB(16TB) for General Purpose/Memory Optimized SKUs.
version	Specifies the version of PostgreSQL to use. Valid values are 9.5, 9.6, 10, 10.0, and 11.
database_name	Specifies the name of the PostgreSQL Database, which needs to be a valid PostgreSQL identifier.
charset	Specifies the Charset for the PostgreSQL Database, which needs to be a valid PostgreSQL Charset..
collation	Specifies the Collation for the PostgreSQL Database, which needs to be a valid PostgreSQL Collation. Note that Microsoft uses different notation - en-US instead of en_US.
admin_username	The Administrator Login for the PostgreSQL Server. Required when create_mode is Default.
admin_password	The Password associated with the admin_username for the PostgreSQL Server. Required when create_mode is Default
auto_grow_enabled	Enable/Disable auto-growing of the storage. Storage auto-grow prevents your server from running out of storage and becoming read-only. If storage auto grow is enabled, the storage automatically grows without impacting the workload. The default value if not explicitly specified is true
backup_retention_days	Backup retention days for the server, supported values are between 7 and 35 days.
geo_redundant_backup_enabled	Turn Geo-redundant server backups on/off. This allows you to choose between locally redundant or geo-redundant backup storage in the General Purpose and Memory Optimized tiers. When the backups are stored in geo-redundant backup storage, they are not only stored within the region in which your server is hosted, but are also replicated to a paired data center. This provides better protection and ability to restore your server in a different region in the event of a disaster. This is not support for the Basic tier.
infrastructure_encryption_enabled	Whether or not infrastructure is encrypted for this server. This property is currently still in development and not supported by Microsoft. If the infrastructure_encryption_enabled attribute is set to true the postgreSQL instance will incur a substantial performance degradation due to a second encryption pass on top of the existing default encryption that is already provided by Azure Storage. It is strongly suggested to leave this value false as not doing so can lead to unclear error messages. Defaults to false
public_network_access_enabled	Whether or not public network access is allowed for this server. Defaults to true.
ssl_enforcement_enabled	Specifies if SSL should be enforced on connections. Possible values are true and false
ssl_minimal_tls_version_enforced	The minimum TLS version to support on the sever. Possible values are TLSEnforcementDisabled, TLS1_0, TLS1_1, and TLS1_2. Defaults to TLSEnforcementDisabled.

Advanced Usage of the Module

postgresql_configuration - Configure PostgreSQL Server Parameters

The PostgreSQL server maintains many system variables that configure its operation. Each system variable has a default value. System variables can be set at server startup using options on the command line or in an option file. Most of them can be changed dynamically at runtime using the SET statement, which enables you to modify operation of the server without having to stop and restart it. You can also use system variable values in expressions.

A few Supported parameters are here for your reference. you can find all these Server Paramter section in PostgreSQL server. Also check PostgreSQL website for more details.

Parameter name	Description	Parameter Type	Default Value
connection_throttling	Enables temporary connection throttling per IP for too many invalid password login failures. Valid values are ON and OFF	Dynamic	ON
deadlock_timeout	Sets the amount of time, in milliseconds, to wait on a lock before checking for deadlock. Allowed value should be: 1-2147483647	Dynamic	1000
log_min_error_statement	Causes all statements generating error at or above this level to be logged.	Dynamic	ERROR
old_snapshot_threshold	Time before a snapshot is too old to read pages changed after the snapshot was taken. Any change requires server restart.	Static	-1

PostgreSQL Virtual Network Rule

A virtual network rule for your Azure Database for PostgreSQL server is a subnet that is listed in the access control list (ACL) of your Azure Database for PostgreSQL server. To be in the ACL for your Azure Database for PostgreSQL server, the subnet must contain the Microsoft.Sql type name. To enable this feature, add a subnet_id with valid resource id.

This feature is available in all regions of Azure public cloud where Azure Database for PostgreSQL is deployed for General Purpose and Memory Optimized servers. In case of VNet peering, if traffic is flowing through a common VNet Gateway with service endpoints and is supposed to flow to the peer, please create an ACL/VNet rule to allow Azure Virtual Machines in the Gateway VNet to access the Azure Database for PostgreSQL server.

Data Encryption with a Customer-managed Key

Data encryption with customer-managed keys for Azure Database for PostgreSQL enables you to bring your own key (BYOK) for data protection at rest. It also allows organizations to implement separation of duties in the management of keys and data.

Data encryption is set at the server-level. The customer-managed key is an asymmetric key stored in a customer-owned and customer-managed Azure Key Vault instance. To add you own key from key valut use variable key_vault_key_id with valid key URL.

Server Firewall Rules

Firewalls prevent all access to your database server until you specify which computers have permission. To configure a firewall, create firewall rules that specify ranges of acceptable IP addresses.

By default, no external access to your PostgreSQL Database will be allowed until you explicitly assign permission by creating a firewall rule. To add the firewall rules to the PostgreSQL database, specify the list of firewall_rules with valid IP addresses.

Adding Active Directory Administrator to PostgreSQL Database

Azure Active Directory authentication is a mechanism of connecting to Microsoft Azure database for PostgreSQL by using identities in Azure Active Directory (Azure AD). This module adds the provided Azure Active Directory user/group to PostgreSQL Database as an administrator so that the user can login to this database with Azure AD authentication.

By default, this feature not enabled on this module. To add the Active Directory Administrator, set the argument ad_admin_login_name with a valid Azure AD user/group login name.

Threat detection policy AKA Server Security Alerts Policy

Advanced Threat Detection for Azure Database for PostgreSQL server detects anomalous activities indicating unusual and potentially harmful attempts to access or exploit databases and it can trigger the following alerts:

• Access from unusual location
• Access from unusual Azure data center
• Access from unfamiliar principal
• Access from a potentially harmful application
• Brute force login credentials

By default, this feature not enabled on this module. Enable threat detection policy setting up the variables enable_threat_detection_policy, log_retention_days and email_addresses_for_alerts with valid values.

Note: Enabling threat_detection_policy features on SQL servers and database going to create a storage account to keep all audit logs by this module. Log retention policy to be configured to keep the size within limits for this storage account. Note that this module creates resources that can cost money.

Recommended naming and tagging conventions

Applying tags to your Azure resources, resource groups, and subscriptions to logically organize them into a taxonomy. Each tag consists of a name and a value pair. For example, you can apply the name Environment and the value Production to all the resources in production. For recommendations on how to implement a tagging strategy, see Resource naming and tagging decision guide.

Important : Tag names are case-insensitive for operations. A tag with a tag name, regardless of the casing, is updated or retrieved. However, the resource provider might keep the casing you provide for the tag name. You'll see that casing in cost reports. Tag values are case-sensitive.

An effective naming convention assembles resource names by using important resource information as parts of a resource's name. For example, using these recommended naming conventions, a public IP resource for a production SharePoint workload is named like this: pip-sharepoint-prod-westus-001.

Requirements

Name	Version
terraform	>= 0.13
azurerm	>= 2.59.0

Providers

Name	Version
azurerm	>= 2.59.0
random	>= 3.1.0

Inputs

Name	Description	Type	Default
create_resource_group	Whether to create resource group and use it for all networking resources	string	"false"
resource_group_name	The name of the resource group in which resources are created	string	""
location	The location of the resource group in which resources are created	string	""
log_analytics_workspace_name	The name of log analytics workspace name	string	null
random_password_length	The desired length of random password created by this module	string	24
subnet_id	The resource ID of the subnet	string	null
postgresql_server_name	PostgreSQL server Name	string	""
admin_username	The username of the local administrator used for the PostgreSQL Server	string	"postgresadmin"
admin_password	The Password which should be used for the local-administrator on this PostgreSQL Server	string	null
identity	If you want your PostgreSQL Server to have an managed identity. Defaults to false	string	false
postgresql_server_settings	PostgreSQL server settings	object({})	{}
create_mode	The creation mode. Can be used to restore or replicate existing servers. Possible values are Default, Replica, GeoRestore, and PointInTimeRestore	string	Default
creation_source_server_id	For creation modes ot her than Default, the source server ID to use	string	null
restore_point_in_time	When create_mode is PointInTimeRestore, specifies the point in time to restore from creation_source_server_id	string	null
storage_account_name	The name of the storage account name	string	null
enable_threat_detection_policy	Threat detection policy configuration, known in the API as Server Security Alerts Policy	string	false
email_addresses_for_alerts	Account administrators email for alerts	list(any)	""
disabled_alerts	Specifies a list of alerts which should be disabled. Possible values include Access_Anomaly, Sql_Injection and Sql_Injection_Vulnerability	list(any)	[]
log_retention_days	Specifies the number of days to keep in the Threat Detection audit logs	number	30
postgresql_configuration	Sets a PostgreSQL Configuration value on a PostgreSQL Server	map(string)	{}
firewall_rules	Range of IP addresses to allow firewall connections	map(object({}))	null
ad_admin_login_name	The login name of the principal to set as the server administrator	string	null
key_vault_key_id	The URL to a Key Vault custom managed key	string	null
enable_private_endpoint	Azure Private Endpoint is a network interface that connects you privately and securely to a service powered by Azure Private Link	string	"false"
virtual_network_name	The name of the virtual network	string	""
private_subnet_address_prefix	A list of subnets address prefixes inside virtual network	list	[]
existing_private_dns_zone	Name of the existing private DNS zone	string	null
Tags	A map of tags to add to all resources	map	{}

Outputs

Name	Description
resource_group_name	The name of the resource group in which resources are created
resource_group_location	The location of the resource group in which resources are created
storage_account_id	The resource ID of the storage account
storage_account_name	The name of the storage account
postgresql_server_id	The resource ID of the PostgreSQL Server
postgresql_server_fqdn	The FQDN of the PostgreSQL Server
postgresql_database_id	The ID of the PostgreSQL Database
postgresql_server_private_endpoint	id of the PostgreSQL server Private Endpoint
postgresql_server_private_dns_zone_domain	DNS zone name of PostgreSQL server Private endpoints dns name records
postgresql_server_private_endpoint_ip	PostgreSQL server private endpoint IPv4 Addresses
postgresql_server_private_endpoint_fqdn	PostgreSQL server private endpoint FQDN Addresses

Resource Graph

Authors

Originally created by Kumaraswamy Vithanala

Other resources

• Azure database for PostgreSQL
• Terraform AzureRM Provider Documentation