Conventions

Purpose: Single definition of the OS groups, filesystem layout and Oracle Home naming that the OraDBA tools assume as defaults.

Audience: DBAs and engineers who install Oracle software with OraDBA tooling, build images or labs, or write automation on top of it.

Introduction

Several repositories install and patch Oracle software: the patch and home engine odb_autoupgrade, the Ansible collection oradba.automation (repository oradba-ansible, planned), lab environments and Docker image builds. This page defines the conventions they share. It is the only place where these values are decided:

• Engine and collection implement them as defaults that a site can override. Site configuration always wins.
• A change to a convention is made on this page first; the implementing repositories follow in their next release.
• Nothing here is an Oracle requirement unless stated. Where Oracle has a default (Preinstallation RPM, OFA), the difference is named.

Scope is single-instance Oracle Database on Linux. Grid Infrastructure and ASM groups (asmadmin, asmdba, asmoper) are not covered yet.

Filesystem Layout

Three roots, kept as separate directories even when they live on one filesystem. Any of them can later move to a dedicated volume without changing a path.

Item	Variable	Default	Notes
Software root	ORACLE_ROOT	/u00	Binaries, ORACLE_BASE, inventory
Data root	ORACLE_DATA	/u01	Datafiles, control files, online redo
Archive root	ORACLE_ARCH	/u02	Archived redo and fast recovery area
ORACLE_BASE	ORACLE_BASE	/u00/app/oracle	Also root of the OraDBA installation (${ORACLE_BASE}/local/oradba)
Central inventory	-	/u00/app/oraInventory	Recorded in /etc/oraInst.loc with inst_group=oinstall
Oracle Homes	ORACLE_HOME	${ORACLE_BASE}/product/<version>	See Oracle Home Naming
Datafiles	-	/u01/oradata/<DB_UNIQUE_NAME>	One directory per database
Archived redo	-	/u02/archive/<DB_UNIQUE_NAME>	When not written to the fast recovery area
Fast recovery area	db_recovery_file_dest	/u02/fast_recovery_area	Oracle adds <DB_UNIQUE_NAME> below

Difference to Oracle OFA: OFA uses /u01/app/oracle for the software and /u02, /u03, ... for data. The OraDBA layout keeps software on /u00 so that /u01 and /u02 carry only database files.

How OraDBA applies these defaults:

• When ORACLE_BASE is unset, OraDBA scripts use /u00/app/oracle (override with ORADBA_DEFAULT_ORACLE_BASE) and print a WARN line.
• oradba_dbca.sh places datafiles in ${ORACLE_DATA}/oradata/<DB_UNIQUE_NAME> and the fast recovery area in ${ORACLE_ARCH}/fast_recovery_area when these variables are set; otherwise below ORACLE_BASE as before. DATA_DIR and FRA_DIR override both.

Known deviation: oracle-database-docker-legacy uses ORACLE_DATA=/u00/oradata (single root).

OS Users and Groups

The software owner is oracle. Group names default to the names created by the Oracle Database Preinstallation RPM (oracle-database-preinstall-19c on Oracle Linux 8 and 9), with the RPM's GIDs.

Role	Default name	GID (RPM)	odb_autoupgrade variable	AutoUpgrade key
Inventory group	oinstall	54321	AU_INVENTORY_GROUP	home_settings.inventory_group
OSDBA	dba	54322	AU_GROUP_OSDBA	home_settings.osdba_group
OSOPER	oper	54323	AU_GROUP_OSOPER	home_settings.osoper_group
OSBACKUPDBA	backupdba	54324	AU_GROUP_OSBACKUPDBA	home_settings.osbackupdba_group
OSDGDBA	dgdba	54325	AU_GROUP_OSDGDBA	home_settings.osdgdba_group
OSKMDBA	kmdba	54326	AU_GROUP_OSKMDBA	home_settings.oskmdba_group
OSRACDBA	racdba	54330	AU_GROUP_OSRACDBA	home_settings.osracdba_group

The user oracle (UID 54321 from the RPM) has oinstall as primary group and all six OS groups as secondary groups. Reference: Oracle Database 19c installation guide for Linux - operating system privileges groups.

Rules:

• GIDs (and the UID of oracle) must be identical on all hosts that share files or form one configuration (Data Guard, shared NFS for backups or patches). Choose them once per site.
• When a home is created from an existing source home, the groups recorded in the source home (rdbms/lib/config.c) win; the defaults above apply only to homes created without a source home.
• The engine uses group names only. GIDs matter where groups are created (OS preparation, the collection).

Site Variant: os* Group Names

Some sites use osdba, osoper, osbackupdba, osdgdba, oskmdba and osracdba with fixed GIDs. This is a supported site choice, not the default. The GIDs of such a site are site data and are not published here; they belong in the site configuration of the group creation. odb_autoupgrade ships the name mapping as an example in etc/groups/os-fixed-gid.env.

Legacy GIDs

oracle-database-docker-legacy creates the default group names with GIDs 1010 (oinstall), 1020 (dba), 1030 (oper), 1040 (backupdba), 1050 (kmdba), 1060 (dgdba) and 1070 (racdba). Images and volumes built with these GIDs keep them until they are rebuilt; changing GIDs on an existing host means re-owning every file of the old GID.

Oracle Home Naming

New database homes are named after the Release Update they contain, in four parts:

${ORACLE_BASE}/product/<major>.<RU>.0.0
/u00/app/oracle/product/19.32.0.0

• The four-part version is the releaseUpdate value from AutoUpgrade's patches_info.json, not the base release.
• A second home on the same RU (for example a different MRP level or one-off set) gets a numeric suffix: product/19.32.0.0_2, product/19.32.0.0_3.
• No dbhome_1 level below the version.
• The home is registered in oradba_homes.conf so that OraDBA can switch to it. odb_autoupgrade does this in OraDBA mode and prints it as a manual step in standalone mode.

Names in use before this convention and to be migrated: product/19.0.0.0 (docker), product/19.31/dbhome_1 (oci-labs). Existing homes are not renamed in place; the convention applies to the next home created out of place.

The convention covers database homes. Other products managed by OraDBA (client, OUD, WebLogic, Data Safe connectors) keep their current names.

Implementation and Overrides

Repository	Implements	Override
oradba	Environment for ORACLE_BASE and registered homes	ORACLE_BASE in the OraDBA configuration, oradba_homes.conf
odb_autoupgrade (0.6.0+)	Group defaults, home naming, inventory	AU_ORACLE_BASE, AU_GROUP_*, AU_INVENTORY_LOCATION, AU_INVENTORY_GROUP, AU_TARGET_HOME
oradba-ansible (planned)	Group and user creation with GIDs, directory layout	Role variables (inventory or site variables)
oci-labs, image builds	Consume the engine and the collection	Lab inventory and build arguments

Details for the engine: odb_autoupgrade - Oracle Home Management.