Centos5.5 explanation of default basic services avahi-daemon

Centos5.5 basic services by default

Service name	Function	Default	Suggestions	Remarks
NetworkManager	Used to automatically connect to the network	Close	Close	Useless to servers
Acpid	Power Switch and other Detection Management	Enable	Close	Useless to servers
Anacron	Scheduled Task Management	Enable	Enable
Apmd	Advanced Power Management	Enable	Enable
ATD	Execute the command at the specified time	Enable	Close	If crond is used, you can disable it.
Auditd		Enable	Custom	If SELinux is used, you need to enable it.
Autofs	Automatic File System loading and unloading	Enable	Custom	You can only enable it as needed and stop it.
Avahi-daemon	Local Network Service search	Enable	Close	Useless to servers
Avahi-dnsconfd	Avahi DNS	Close	Close	Useless to servers
Bluetooth	Bluetooth Wireless Communication	Enable	Close	Useless to servers
Conman	Console Management	Close	Close	Useless
Spuspeed	CPU speed adjustment	Enable	Custom
Crond	Scheduled Task Management	Enable	Enable	Very useful. Enable
Cups	General UNIX Printing Service	Enable	Close	Useless to servers
Dnsmasq	DNS Cache	Close	Close	Useless
Dund	Bluetooth Problems	Close	Close
Firstboot	Initial settings after system installation	Enable	Close
GPM	Mouse support in the console	Enable	Enable
Haldaemon	Hardware information collection service	Enable	Enable
Hidd	Bluetooth Problems	Enable	Close
Ibmasm	IBM Hardware Management	Close	Close
Ip6tables	IPv6 Firewall	Enable	Close
Iptables	IPv4 Firewall	Enable	Close
IRDA	Infrared Communication	Close	Close
Irqbalance	CPU load balancing	Enable	Custom	Multi-core CPU
Kudzu	Hardware Change Detection	Enable	Close	Useless Server
Lvm2-monitor	LVM monitoring	Enable	Close	Non-cluster useless
Mcstrans	Used to check context when SELinux is enabled	Enable	Close
Mdmonitor	Soft Raid monitoring	Enable	Close
Mdmpd	Soft Raid Management	Close	Close
Messagebus	Transmits messages between various system processes.	Enable	Enable	If disabled, haldaemon fails to start.
Microcode_ctl	CPU microcode management upgrade	Enable	Close
Multipathd		Close	Close
Netconsole		Close	Close
Netfs	NFS Problems	Enable	Close
Netplugd	Network hot swapping monitoring	Close	Close
Network		Enable	Enable
NFS	Network File System	Close	Close
Nfslock	NFS Problems	Enable	Close
Nscd	Name cache, which should be related to DNS	Close	Close
Oddjobd	Related to D-BUS	Close	Close
Pand	Bluetooth Problems	Close	Close
Pcscd	PC/SC Smart Card daemon	Enable	Close
Portmap	Port map when NFS and NIS are used	Enable	Close
Psacct	Load detection	Close	Close
Rawdevices	Raw Device Support	Enable	Enable
Rdisc	Automatic Router Detection	Close	Close
Readahead_early		Enable	Enable
Readahead_later		Close	Close
Restorecond	SELinux Problems	Close	Close
Rpcgssd	NFS Problems	Enable	Close
Rpcidmapd	RPC name to UID/GID mapper	Enable	Close	NFS Problems
Rpcsvcgssd	NFS Problems	Close	Close
Saslauthd	SASL Certification Service	Close	Close
Sendmail		Enable	Close
Smartd	Hard Disk Automatic Detection daemon	Enable	Enable
Sshd		Enable	Enable
Syslog	System log process	Enable	Enable
Tcsd		Close	Close
Wpa_supplicant	Wireless authentication	Close	Close
XFS	X Windows	Enable	Close
Ypbind	Network Information Service Client	Close	Close
Yum-updatesd	Automatic Yum upgrade	Enable	Close	It is dangerous to enable the server.

Note: The above service list is displayed on the premise that only basic systems, development tools, development libraries, and old software support are installed in centos.

Avahi-daemon

 

Zeroconf
Zero Configuration networking (zeroconf) is a network technology used to automatically generate available IP addresses. No additional manual configuration or exclusive configuration server is required.

The goal of "zero-configuration Network Service" is to allow non-professional users to easily connect to various network devices, such as computers and printers. The entire network construction process is automated through the program. If there is no zeroconf, you must manually configure some services, such as DHCP, DNS, and other computer network settings. These are difficult for non-technical users and new users.

The author of zeroconf specifications is apple.

Avahi
Avahi is an open-source implementation of zeroconf specifications, which is commonly used in Linux. Includes the implementation of a complete set of multicast DNS (multicastdns)/DNS-SD network services. It uses the publish authorization lgpl. Another implementation of zeroconf specifications is Apple's bonjour program. Avahi And bonjour are compatible with each other (all nonsense follows the same standard, just like IE, Firefox, and chrome can run http1.1 ).

Avahi allows programs to publish and learn various services and hosts in a local network without manual network configuration. For example, when a user connects his computer to a LAN, if the user runs the avahi service, the avahi program automatically broadcasts, this allows you to find printers, shared files, and other users that can chat with each other. This is a bit like he is receiving various network advertisements in the LAN.

The actual process started in Linux is named avahi-daemon.

Disable it unless you have compatible devices or services that use the zeroconf protocol. If you cannot use it, close the service directly.
/Etc/init. d/avahi-daemon stop or service avahi-daemon stop

Switch off: chkconfig avahi-daemon off