Error
Error Code: ORA-30155

Oracle I/O Error

📦 Oracle Database
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Description

The ORA-30155 error indicates a low-level input/output (I/O) problem within the Oracle database. This error commonly arises when the database attempts to read from or write to files on the operating system, and the operation fails.
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Error Message

ORA-30155: An I/O Error occurred during an OCIFile function call
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Known Causes

4 known causes
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Disk Space Exhaustion
The database server might run out of available disk space, preventing it from writing data to necessary files.
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File Permissions Issue
The Oracle database user account might lack the necessary permissions to read from or write to the files or directories it needs to access.
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Hardware Failure
Underlying hardware issues, such as disk drive failure or network connectivity problems, can lead to I/O errors.
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File System Corruption
Corruption within the file system can cause I/O operations to fail when the database attempts to access specific files.
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Solutions

4 solutions available

1. Verify File System Permissions easy

Ensures the Oracle user has read/write access to the affected directory.

1
Identify the directory or file that the OCIFile function is trying to access. This information might be found in Oracle trace files, alert logs, or application logs. Common locations include directories for Oracle Managed Files (OMF), external tables, or Oracle Data Pump.
2
Log in to the operating system where the Oracle database is running as a user with sufficient privileges (e.g., root or a user with sudo access).
3
Check the ownership and permissions of the directory/file. The Oracle software owner (usually `oracle`) must have read and write permissions.
ls -ld /path/to/directory_or_file
4
If permissions are incorrect, change them to grant the Oracle user read and write access.
sudo chown -R oracle:oinstall /path/to/directory_or_file
sudo chmod -R 775 /path/to/directory_or_file
5
Restart the Oracle process or application that encountered the error to re-test the fix.

2. Check Disk Space and File System Health medium

Confirms that the underlying file system has sufficient space and is not experiencing corruption.

1
Identify the file system where the Oracle data files, redo logs, archive logs, or other files accessed by OCIFile functions reside.
2
Check the available disk space on the relevant file system.
df -h
3
If disk space is low, free up space by deleting unnecessary files, moving data, or adding more storage.
4
Examine the operating system logs (e.g., `/var/log/messages`, `/var/log/syslog`) for any file system errors or disk I/O issues.
5
If file system corruption is suspected, consider running file system check utilities (e.g., `fsck` on Linux/Unix) during a maintenance window.
sudo fsck /dev/sdXY
6
Restart the Oracle database or the affected application component after resolving disk space or file system issues.

3. Investigate Oracle Alert Log and Trace Files medium

Analyzes Oracle's internal logs for more specific I/O error details.

1
Locate the Oracle alert log file. This is typically found in the `ADR_HOME/diag/rdbms/<dbname>/<instance>/trace` directory or specified by the `ALERTLOG` parameter in the `init.ora` or `spfile`.
2
Search the alert log for entries related to ORA-30155 around the time the error occurred. The alert log often provides more context, including the specific OCIFile function call and the path to the file involved.
grep 'ORA-30155' /path/to/alert_<dbname>.log
3
If trace files are mentioned in the alert log, locate and examine them. Trace files can contain detailed stack traces and I/O operation information.
4
Look for underlying operating system error codes within the trace files or alert log messages. These codes can provide clues about the nature of the I/O failure (e.g., disk full, hardware error, network issue if using network storage).
5
Based on the findings in the logs, implement the appropriate solution (e.g., adjust permissions, address disk space, investigate hardware).

4. Validate Oracle Managed Files (OMF) Configuration medium

Reviews settings for Oracle Managed Files if they are in use.

1
Determine if Oracle Managed Files (OMF) are enabled for your database. You can check this by querying the `DB_FILES_RECYCLEBIN` and `DB_FILE_NAME_CONVERT` parameters.
SHOW PARAMETER DB_FILES_RECYCLEBIN;
SHOW PARAMETER DB_FILE_NAME_CONVERT;
2
If OMF is enabled, verify the `DB_CREATE_FILE_DEST` parameter is correctly set to a valid and accessible directory.
SHOW PARAMETER DB_CREATE_FILE_DEST;
3
Ensure the Oracle software owner has read/write/execute permissions on the directory specified by `DB_CREATE_FILE_DEST` and any other directories used by OMF (e.g., for archive logs if `DB_RECOVERY_FILE_DEST` is also an OMF location).
ls -ld /path/to/omf_directory
4
Check if the `DB_CREATE_FILE_DEST` directory has sufficient free space.
df -h /path/to/omf_directory
5
If the `DB_CREATE_FILE_DEST` is incorrect or inaccessible, correct it using `ALTER SYSTEM` and restart the instance if necessary.
ALTER SYSTEM SET DB_CREATE_FILE_DEST = '/new/path/to/omf_directory' SCOPE=SPFILE;
-- Then restart the database