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Overview

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The SAP on Azure Deployment Automation Framework uses a standard naming convention for Azure resource naming.

The Terraform module sap_namegenerator defines the names of all resources that the automation framework deploys. The module is located at /deploy/terraform/terraform-units/modules/sap_namegenerator/ in the repository. The framework also supports providing your own names for some of the resources using the parameter files.

The naming of the resources uses the following format:

resource prefix + resource_group_prefix + separator + resource name + resource suffix.

If these capabilities are not enough, you can also use custom naming logic by either providing a custom json file containing the resource names or by modifying the naming module used by the automation.

Provide name overrides using a json file

You can specify a custom naming json file in your tfvars parameter file using the 'name_override_file' parameter.

The json file has sections for the different resource types.

The deployment types are:

  • DEPLOYER (Control Plane)
  • SDU (SAP System Infrastructure)
  • WORKLOAD_ZONE (Workload zone)

Availability set names

The names for the availability sets are defined in the "availabilityset_names" structure. The example below lists the availability set names for a deployment.

  "availabilityset_names" : {
        "app": "app-avset",
        "db" : "db-avset",
        "scs": "scs-avset",
        "web": "web-avset"
    }

Key Vault names

The names for the key vaults are defined in the "keyvault_names" structure. The example below lists the key vault names for a deployment in the "DEV" environment in West Europe.

"keyvault_names": {
        "DEPLOYER": {
            "private_access": "DEVWEEUprvtABC",
            "user_access": "DEVWEEUuserABC"
        },
        "SDU": {
            "private_access": "DEVWEEUSAP01X00pABC",
            "user_access": "DEVWEEUSAP01X00uABC"
        },
        "WORKLOAD_ZONE": {
            "private_access": "DEVWEEUSAP01prvtABC",
            "user_access": "DEVWEEUSAP01userABC"
        }
    }

Note

This key vault names need to be unique across Azure, SAP on Azure Deployment Automation Framework appends 3 random characters (ABC in the example) at the end of the key vault name to reduce the likelihood for name conflicts.

The "private_access" names are currently not used.

Storage Account names

The names for the storage accounts are defined in the "storageaccount_names" structure. The example below lists the storage account names for a deployment in the "DEV" environment in West Europe.

"storageaccount_names": {
        "DEPLOYER": "devweeudiagabc",
        "LIBRARY": {
            "library_storageaccount_name": "devweeusaplibabc",
            "terraformstate_storageaccount_name": "devweeutfstateabc"
        },
        "SDU": "devweeusap01diagabc",
        "WORKLOAD_ZONE": {
            "landscape_shared_transport_storage_account_name": "devweeusap01sharedabc",
            "landscape_storageaccount_name": "devweeusap01diagabc",
            "witness_storageaccount_name": "devweeusap01witnessabc"
        }
    }

Note

This key vault names need to be unique across Azure, SAP on Azure Deployment Automation Framework appends 3 random characters (abc in the example) at the end of the key vault name to reduce the likelihood for name conflicts.

Virtual Machine names

The names for the virtual machines are defined in the "virtualmachine_names" structure. Both the computer and the virtual machine names can be provided.

The example below lists the virtual machine names for a deployment in the "DEV" environment in West Europe. The deployment has a database server, two application servers, a Central Services server and a web dispatcher.

    "virtualmachine_names": {
        "ANCHOR_COMPUTERNAME": [],
        "ANCHOR_SECONDARY_DNSNAME": [],
        "ANCHOR_VMNAME": [],
        "ANYDB_COMPUTERNAME": [
            "x00db00l0abc"
        ],
        "ANYDB_SECONDARY_DNSNAME": [
            "x00dhdb00l0abc",
            "x00dhdb00l1abc"
        ],
        "ANYDB_VMNAME": [
            "x00db00l0abc"
        ],
        "APP_COMPUTERNAME": [
            "x00app00labc",
            "x00app01labc"
        ],
        "APP_SECONDARY_DNSNAME": [
            "x00app00labc",
            "x00app01labc"
        ],
        "APP_VMNAME": [
            "x00app00labc",
            "x00app01labc"
        ],
        "DEPLOYER": [
            "devweeudeploy00"
        ],
        "HANA_COMPUTERNAME": [
            "x00dhdb00l0af"
        ],
        "HANA_SECONDARY_DNSNAME": [
            "x00dhdb00l0abc"
        ],
        "HANA_VMNAME": [
            "x00dhdb00l0abc"
        ],
        "ISCSI_COMPUTERNAME": [
            "devsap01weeuiscsi00"
        ],
        "OBSERVER_COMPUTERNAME": [
            "x00observer00labc"
        ],
        "OBSERVER_VMNAME": [
            "x00observer00labc"
        ],
        "SCS_COMPUTERNAME": [
            "x00scs00labc"
        ],
        "SCS_SECONDARY_DNSNAME": [
            "x00scs00labc"
        ],
        "SCS_VMNAME": [
            "x00scs00labc"
        ],
        "WEB_COMPUTERNAME": [
            "x00web00labc"
        ],
        "WEB_SECONDARY_DNSNAME": [
            "x00web00labc"
        ],
        "WEB_VMNAME": [
            "x00web00labc"
        ]
    }

Configure custom naming module

There are multiple files within the module for naming resources:

  • Virtual machine (VM) and computer names are defined in (vm.tf)
  • Resource group naming is defined in (resourcegroup.tf)
  • Key vaults in (keyvault.tf)
  • Resource suffixes (variables_local.tf)

The different resource names are identified by prefixes in the Terraform code.

  • SAP deployer deployments use resource names with the prefix deployer_
  • SAP library deployments use resource names with the prefix library
  • SAP landscape deployments use resource names with the prefix vnet_
  • SAP system deployments use resource names with the prefix sdu_

The calculated names are returned in a data dictionary, which is used by all the terraform modules.

Using custom names

Some of the resource names can be changed by providing parameters in the tfvars parameter file.

Resource Parameter Notes
Prefix custom_prefix This is used as prefix for all the resources in the resource group
Resource group resourcegroup_name
admin subnet name admin_subnet_name
admin nsg name admin_subnet_nsg_name
db subnet name db_subnet_name
db nsg name db_subnet_nsg_name
app subnet name app_subnet_name
app nsg name app_subnet_nsg_name
web subnet name web_subnet_name
web nsg name web_subnet_nsg_name
admin nsg name admin_subnet_nsg_name

Changing the naming module

To prepare your Terraform environment for custom naming, you first need to create custom naming module. The easiest way is to copy the existing module and make the required changes in the copied module.

  1. Create a root-level folder in your Terraform environment. For example, Azure_SAP_Automated_Deployment.
  2. Navigate to your new root-level folder.
  3. Clone the automation framework repository. This step creates a new folder sap-automation.
  4. Create a folder within the root-level folder called Contoso_naming.
  5. Navigate to the sap-automation folder.
  6. Check out the appropriate branch in git.
  7. Navigate to \deploy\terraform\terraform-units\modules within the sap-automation folder.
  8. Copy the folder sap_namegenerator to the Contoso_naming folder.

The naming module is called from the root terraform folders:

module "sap_namegenerator" {
  source           = "../../terraform-units/modules/sap_namegenerator"
  environment      = local.infrastructure.environment
  location         = local.infrastructure.region
  codename         = lower(try(local.infrastructure.codename, ""))
  random_id        = module.common_infrastructure.random_id
  sap_vnet_name    = local.vnet_logical_name
  sap_sid          = local.sap_sid
  db_sid           = local.db_sid
  app_ostype       = try(local.application.os.os_type, "LINUX")
  anchor_ostype    = upper(try(local.anchor_vms.os.os_type, "LINUX"))
  db_ostype        = try(local.databases[0].os.os_type, "LINUX")
  db_server_count  = var.database_server_count
  app_server_count = try(local.application.application_server_count, 0)
  web_server_count = try(local.application.webdispatcher_count, 0)
  scs_server_count = local.application.scs_high_availability ? 2 * local.application.scs_server_count : local.application.scs_server_count
  app_zones        = local.app_zones
  scs_zones        = local.scs_zones
  web_zones        = local.web_zones
  db_zones         = local.db_zones
  resource_offset  = try(var.options.resource_offset, 0)
  custom_prefix    = var.custom_prefix
}

Next, you need to point your other Terraform module files to your custom naming module. These module files include:

  • deploy\terraform\run\sap_system\module.tf
  • deploy\terraform\bootstrap\sap_deployer\module.tf
  • deploy\terraform\bootstrap\sap_library\module.tf
  • deploy\terraform\run\sap_library\module.tf
  • deploy\terraform\run\sap_deployer\module.tf

For each file, change the source for the module sap_namegenerator to point to your new naming module's location. For example:

module "sap_namegenerator" { source = "../../terraform-units/modules/sap_namegenerator" becomes module "sap_namegenerator" { source = "../../../../Contoso_naming".

Change resource group naming logic

To change your resource group's naming logic, navigate to your custom naming module folder (for example, Workspaces\Contoso_naming). Then, edit the file resourcegroup.tf. Modify the following code with your own naming logic.

locals {

  // Resource group naming
  sdu_name = length(var.codename) > 0 ? (
    upper(format("%s-%s-%s_%s-%s", local.env_verified, local.location_short, local.sap_vnet_verified, var.codename, var.sap_sid))) : (
    upper(format("%s-%s-%s-%s", local.env_verified, local.location_short, local.sap_vnet_verified, var.sap_sid))
  )

  deployer_name  = upper(format("%s-%s-%s", local.deployer_env_verified, local.deployer_location_short, local.dep_vnet_verified))
  landscape_name = upper(format("%s-%s-%s", local.landscape_env_verified, local.location_short, local.sap_vnet_verified))
  library_name   = upper(format("%s-%s", local.library_env_verified, local.location_short))

  // Storage account names must be between 3 and 24 characters in length and use numbers and lower-case letters only. The name must be unique.
  deployer_storageaccount_name       = substr(replace(lower(format("%s%s%sdiag%s", local.deployer_env_verified, local.deployer_location_short, local.dep_vnet_verified, local.random_id_verified)), "/[^a-z0-9]/", ""), 0, var.azlimits.stgaccnt)
  landscape_storageaccount_name      = substr(replace(lower(format("%s%s%sdiag%s", local.landscape_env_verified, local.location_short, local.sap_vnet_verified, local.random_id_verified)), "/[^a-z0-9]/", ""), 0, var.azlimits.stgaccnt)
  library_storageaccount_name        = substr(replace(lower(format("%s%ssaplib%s", local.library_env_verified, local.location_short, local.random_id_verified)), "/[^a-z0-9]/", ""), 0, var.azlimits.stgaccnt)
  sdu_storageaccount_name            = substr(replace(lower(format("%s%s%sdiag%s", local.env_verified, local.location_short, local.sap_vnet_verified, local.random_id_verified)), "/[^a-z0-9]/", ""), 0, var.azlimits.stgaccnt)
  terraformstate_storageaccount_name = substr(replace(lower(format("%s%stfstate%s", local.library_env_verified, local.location_short, local.random_id_verified)), "/[^a-z0-9]/", ""), 0, var.azlimits.stgaccnt)

}

Change resource suffixes

To change your resource suffixes, navigate to your custom naming module folder (for example, Workspaces\Contoso_naming). Then, edit the file variables_local.tf. Modify the following map with your own resource suffixes.

Note

Only change the map values. Don't change the map key, which the Terraform code uses. For example, if you want to rename the administrator network interface component, change "admin-nic" = "-admin-nic" to "admin-nic" = "yourNICname".

variable resource_suffixes {
  type        = map(string)
  description = "Extension of resource name"

  default = {
    "admin_nic"           = "-admin-nic"
    "admin_subnet"        = "admin-subnet"
    "admin_subnet_nsg"    = "adminSubnet-nsg"
    "app_alb"             = "app-alb"
    "app_avset"           = "app-avset"
    "app_subnet"          = "app-subnet"
    "app_subnet_nsg"      = "appSubnet-nsg"
    "db_alb"              = "db-alb"
    "db_alb_bepool"       = "dbAlb-bePool"
    "db_alb_feip"         = "dbAlb-feip"
    "db_alb_hp"           = "dbAlb-hp"
    "db_alb_rule"         = "dbAlb-rule_"
    "db_avset"            = "db-avset"
    "db_nic"              = "-db-nic"
    "db_subnet"           = "db-subnet"
    "db_subnet_nsg"       = "dbSubnet-nsg"
    "deployer_rg"         = "-INFRASTRUCTURE"
    "deployer_state"      = "_DEPLOYER.terraform.tfstate"
    "deployer_subnet"     = "_deployment-subnet"
    "deployer_subnet_nsg" = "_deployment-nsg"
    "iscsi_subnet"        = "iscsi-subnet"
    "iscsi_subnet_nsg"    = "iscsiSubnet-nsg"
    "library_rg"          = "-SAP_LIBRARY"
    "library_state"       = "_SAP-LIBRARY.terraform.tfstate"
    "kv"                  = ""
    "msi"                 = "-msi"
    "nic"                 = "-nic"
    "osdisk"              = "-OsDisk"
    "pip"                 = "-pip"
    "ppg"                 = "-ppg"
    "sapbits"             = "sapbits"
    "storage_nic"         = "-storage-nic"
    "storage_subnet"      = "_storage-subnet"
    "storage_subnet_nsg"  = "_storageSubnet-nsg"
    "scs_alb"             = "scs-alb"
    "scs_alb_bepool"      = "scsAlb-bePool"
    "scs_alb_feip"        = "scsAlb-feip"
    "scs_alb_hp"          = "scsAlb-hp"
    "scs_alb_rule"        = "scsAlb-rule_"
    "scs_avset"           = "scs-avset"
    "scs_ers_feip"        = "scsErs-feip"
    "scs_ers_hp"          = "scsErs-hp"
    "scs_ers_rule"        = "scsErs-rule_"
    "scs_scs_rule"        = "scsScs-rule_"
    "sdu_rg"              = ""
    "tfstate"             = "tfstate"
    "vm"                  = ""
    "vnet"                = "-vnet"
    "vnet_rg"             = "-INFRASTRUCTURE"
    "web_alb"             = "web-alb"
    "web_alb_bepool"      = "webAlb-bePool"
    "web_alb_feip"        = "webAlb-feip"
    "web_alb_hp"          = "webAlb-hp"
    "web_alb_inrule"      = "webAlb-inRule"
    "web_avset"           = "web-avset"
    "web_subnet"          = "web-subnet"
    "web_subnet_nsg"      = "webSubnet-nsg"

  }
}

Next steps

Learn about naming conventions