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When attempting to start a PostgreSQL 9.3 instance on Ubuntu 12.04 using:

service postgresql start

The system returns:

* The PostgreSQL server failed to start. Please check the log output. [fail]

Yet the expected log file remains empty:

tail /var/log/postgresql/postgresql-9.3-main.log

When PostgreSQL fails to create logs, we need to verify fundamental service configurations:

# Check if PostgreSQL is actually attempting to write logs
psql -U postgres -c "SHOW log_directory;"
psql -U postgres -c "SHOW logging_collector;"

PostgreSQL may be logging elsewhere due to permission issues:

# System-level logs
grep postgres /var/log/syslog
# Kernel messages
dmesg | grep -i postgres

Bypass init scripts to get raw error output:

sudo -u postgres /usr/lib/postgresql/9.3/bin/postgres -D /var/lib/postgresql/9.3/main \
-c config_file=/etc/postgresql/9.3/main/postgresql.conf

• Incorrect permissions on /var/log/postgresql/

  sudo chown postgres:postgres /var/log/postgresql/
  sudo chmod 750 /var/log/postgresql/

• Missing log directory in postgresql.conf

  logging_collector = on
  log_directory = '/var/log/postgresql'

# Verify data directory permissions
namei -l /var/lib/postgresql/9.3/main

# Check for port conflicts
netstat -tulnp | grep 5432

# Validate config file syntax
sudo -u postgres /usr/lib/postgresql/9.3/bin/postgres \
--config-file=/etc/postgresql/9.3/main/postgresql.conf --check

Enable debug-level logging temporarily:

sudo -u postgres psql -c "ALTER SYSTEM SET log_min_messages TO 'debug5';"
sudo service postgresql restart

Then immediately check both standard output and system logs for any error messages.

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When attempting to start PostgreSQL 9.3 on Ubuntu 12.04 with service postgresql start, the service fails silently without generating any log output in /var/log/postgresql/postgresql-9.3-main.log. This creates a particularly frustrating debugging scenario where we have zero visibility into the failure cause.

Before diving deep, let's perform basic sanity checks:

# Check if PostgreSQL is already running
ps aux | grep postgres

# Verify data directory permissions (default location)
ls -ld /var/lib/postgresql/9.3/main

# Check available disk space
df -h /var/lib/postgresql

When standard logging fails, we need to manually force logging through these approaches:

# Method 1: Start postgres manually with logging to stderr
sudo -u postgres /usr/lib/postgresql/9.3/bin/postgres -D /var/lib/postgresql/9.3/main -c config_file=/etc/postgresql/9.3/main/postgresql.conf

# Method 2: Enable debug logging temporarily
echo "log_min_messages = debug5" | sudo tee -a /etc/postgresql/9.3/main/postgresql.conf
service postgresql restart

Permission Issues

The most frequent cause of silent failures:

# Repair ownership recursively
sudo chown -R postgres:postgres /var/lib/postgresql/9.3/main
sudo chmod -R 0700 /var/lib/postgresql/9.3/main

Port Conflicts

# Check for port 5432 usage
sudo netstat -tulnp | grep 5432

# Alternative port test
sudo -u postgres psql -p 5433 -c "SELECT version();"

Corrupted Configuration

Validate config files:

# Check config syntax
sudo -u postgres /usr/lib/postgresql/9.3/bin/postgres -D /var/lib/postgresql/9.3/main -C config_file=/etc/postgresql/9.3/main/postgresql.conf --check-config

Strace for System Calls

# Trace the startup process
sudo strace -f -o /tmp/postgres_strace.log sudo -u postgres /usr/lib/postgresql/9.3/bin/postgres -D /var/lib/postgresql/9.3/main

Checking System Journal

Modern systems might log to journald:

journalctl -u postgresql | tail -20

When all else fails, consider these nuclear options:

# Reinitialize the cluster
sudo pg_dropcluster 9.3 main --stop
sudo pg_createcluster 9.3 main --start

# Verify with
sudo pg_lsclusters