When installed via yum on RHEL/CentOS systems, Memcached typically doesn't write to a dedicated log file by default. The service outputs its logs through syslog, which might not be ideal for debugging or monitoring purposes.
The most straightforward method is to modify the /etc/sysconfig/memcached file. Add the following parameter to the OPTIONS variable:
OPTIONS="-vv >> /var/log/memcached.log 2>&1"
This configuration will:
- Enable verbose logging (-vv)
- Redirect both stdout and stderr to your specified log file
For newer systems using systemd, you can configure journald to handle Memcached logs:
# Create a dedicated config file
sudo mkdir -p /etc/systemd/system/memcached.service.d
sudo tee /etc/systemd/system/memcached.service.d/logging.conf <To prevent log files from growing indefinitely, create a logrotate configuration:
sudo tee /etc/logrotate.d/memcached <If logs aren't appearing as expected:
- Verify file permissions:
sudo chown memcached:memcached /var/log/memcached.log - Check SELinux context:
sudo chcon -t memcache_log_t /var/log/memcached.log - Restart the service:
sudo systemctl restart memcached
For more advanced logging setups, you can configure rsyslog to filter Memcached messages:
# Create a rsyslog config file
sudo tee /etc/rsyslog.d/memcached.conf <When running memcached through the default RHEL/CentOS package installation, logging behavior differs from manual compilation. The yum-installed version uses syslog by default rather than writing to a dedicated file.
To redirect memcached logs to a specific file, you'll need to modify both the init script and syslog configuration:
# First, edit /etc/sysconfig/memcached
OPTIONS="-vv >> /var/log/memcached.log 2>&1"
For more robust logging management, configure rsyslog:
# Create /etc/rsyslog.d/memcached.conf
:programname, isequal, "memcached" /var/log/memcached.log
& stop
Add this to /etc/logrotate.d/memcached for proper log management:
/var/log/memcached.log {
weekly
missingok
rotate 12
compress
delaycompress
notifempty
create 644 memcached memcached
}
After making changes, restart services in this order:
service rsyslog restart
service memcached restart
Check the new log file with:
tail -f /var/log/memcached.log