How to troubleshoot MetaDefender Core Service startup issues in Linux?

Issue: The MetaDefender Core service (ometascan) fails to start. This issue can be caused by various reasons, such as incorrect configuration settings, permission issues, or missing dependencies.

Symptoms:

• MetaDefender Core service fails to start or crashes immediately after starting.
• Error messages related to PostgreSQL or configuration files appear in system logs.
• Logs indicate permission errors or misconfigured parameters.
• The service remains in a stopped state after an attempted restart.

Common Causes and Solutions:

1. Incorrect Permissions on PostgreSQL Configuration Files

Cause: If the postgresql.conf or related files are modified using the root account, the MetaDefender Core service may not have the required permissions to read them.

Solution:

1. Check the ownership and permissions of the PostgreSQL configuration files:

ls -l /var/lib/ometascan/pg_data/postgresql.conf

2. Ensure that the owner is the ometascan user:

chown metascan:metascan /var/lib/ometascan/pg_data/postgresql.conf

sudo chmod 644 /var/lib/ometascan/pg_data/postgresql.conf

3. Restart the MetaDefender Core service:

systemctl restart ometascan.service

2. Customizing PostgreSQL Configuration

Cause: If users need to customize the PostgreSQL configuration without modifying the default postgresql.conf file.

Solution:

1. Instead of modifying /var/lib/ometascan/pg_data/postgresql.conf, create a new configuration file:

sudo touch /usr/lib/ometascan/postgres/postgresql.conf

2. Add the required configuration settings to this file.
3. Ensure the correct ownership and permissions:

chown metascan:metascan /usr/lib/ometascan/postgres/postgresql.conf

chmod 644 /usr/lib/ometascan/postgres/postgresql.conf

4. Restart the MetaDefender Core service:

systemctl restart ometascan.service

3. Invalid Parameter in MetaDefender Core Configuration File

Cause: If the customer adds an incorrect or unsupported parameter in the MetaDefender Core configuration file, the service may fail to start.

Solution:

1. Check the MetaDefender Core logs for error messages related to invalid configuration parameters:

cat /var/log/ometascan/ometascan.log | grep error

2. Review the MetaDefender Core configuration file (/etc/ometascan/ometascan.conf) and ensure all parameters are correctly set.
3. If unsure, revert the configuration file to its default state and restart the service:

mv /etc/ometascan/ometascan.conf /etc/ometascan/ometascan.conf.bak

cp /etc/ometascan/ometascan.conf.default /etc/ometascan/ometascan.conf

systemctl restart ometascan.service

4. PostgreSQL Database Not Running or Corrupted

Cause: The MetaDefender Core service may fail to start if the required PostgreSQL database is not running or is corrupted.

Solution:

1. Check the status of the PostgreSQL service:

systemctl status ometascan-pg.service

2. If PostgreSQL is not running, start it:

systemctl start ometascan-pg.service

3. If the database is corrupted, consider restoring from a backup (-d option should be point to your db.
   1. If using standalone: it will be metadefender_core_xxx with xxx is the first six letters of the deployment id after MSCW in lowercase.
   2. If using shared: it will be metadefender_core:

pg_restore -U postgres -d ometascan /backup/ometascan.dump

5. MetaDefender Core Service Fails Due to Port Conflicts

Cause: If another application is using the same port as the MetaDefender Core service, the service will fail to bind to its configured port.

Solution:

1. Check for port conflicts:

netstat -tulnp | grep <OMT_PORT>

2. If another process is using the port, either stop the conflicting service or change the MetaDefender Core port in /etc/ometascan/ometascan.conf.
3. Restart the MetaDefender Core service:

systemctl restart ometascan.service

Additional Troubleshooting Steps:

• Check system logs for additional clues:

journalctl -xe | grep ometascan.service

• Ensure all dependencies are installed and up to date.
• Verify disk space availability using df -h.

If the issue persists, contact technical support with relevant log files and error messages.