Some unnecessary default services should be turned off in CentOS
How CentOS shuts down services:
chkconfig –level 2345 service_name off
CentOS [CC BY-SA 3.0], via Wikimedia Commons
| service-name | Suggest | Description |
| acpid | Disable | Advanced Configuration and Power Interface Advanced power settings, commonly used on Laptop |
| apmd | Disable | The Advantage Power Management daemon detects the battery level of the system and is commonly used on laptops |
| etc | Disable | /etc/at.allow, /etc/at.deny, I probably use crond to achieve |
| autofs | Disable | Automatically mount the file system and peripheral devices (such as CD-ROM, USB), commonly used on Laptop |
| avahi-daemon | Disable | When the local area network does not have a DNS service, it will try to find the host that provides the zeroconf protocol. |
| bluetooth | Disable | Bluetooth, commonly used on Laptop |
| cpuspeed | Disable | Controlling CPU speed is mainly used to save power and is commonly used on laptops |
| cups | Disable | Common UNIX Printing System |
| firstboot | Disable | Services for the first startup after installation, set auth, firewall, keyboard … |
| gpm | Disable | Record file data of peripheral devices, such as a mouse in text mode |
| haldaemon | Disable | Make the system support plug and play devices |
| trust | Disable | Make the system support Bluetooth devices, such as a mouse, keyboard |
| hplip | Disable | Make the system support HP related printers |
| ip6tables | Disable | Enable the system to support IPTables Firewall IPv6 |
| isdn | Disable | Enabling the system to support the Integrated Services Digital Network (ISDN) environment |
| lm_sensors | Disable | Enable the system to detect the host version or hardware, commonly used on Laptop |
| messagebus | Disable | Make the system support plug and play devices |
| nfslock | Disable | Make the system support NFS Server data consistency function |
| pcscd | Disable | Make the system support Smart Card |
| portmap | Disable | Make the system support NFS Service |
| rpcgssd | Disable | Make the system support NFSv4 Service |
| rpcidmapd | Disable | Make the system support NFSv4 Service |
| yum-updatesd | Disable | Make the system support YUM automatic update service |
