[Linux] 常用命令之【hostname】
1: 个人的片面理解: hostname是主机名(的"昵称"),而非域名。一般设置hostname,来标识当前机器的主要用途、以区别与其它机器
2: hostname
的严格定义: Hostname用于显示系统的DNS名称,以及显示或设置系统的主机名或NIS域名。
Hostname is used to display the system's DNS name, and to display or set its hostname or NIS domain name.
1 查看 hostname
- 方法1: hostname
hostname
2 修改 hostname
- 方法1: hostnamectl
无需重启只需新开会话便可变为新的主机名.
hostnamectl set-hostname 新的主机名
- 方法2: hostname
无需重启只需新开会话便可变为新的主机名.
hostname 新主机名
- 方法3: /etc/hostname
vi /etc/hostname
node116 编辑主机名
vi /etc/sysconfig/network
192.168.1.116 node116 # 添加IP和hostname对应关系
reboot
重启后生效
3 hostname命令详解
# man hostname
HOSTNAME(1) Linux Programmer's Manual HOSTNAME(1)
NAME
hostname - show or set the system's host name
domainname - show or set the system's NIS/YP domain name
ypdomainname - show or set the system's NIS/YP domain name
nisdomainname - show or set the system's NIS/YP domain name
dnsdomainname - show the system's DNS domain name
SYNOPSIS
hostname [-a|--alias] [-d|--domain] [-f|--fqdn|--long] [-A|--all-fqdns] [-i|--ip-address] [-I|--all-ip-addresses] [-s|--short] [-y|--yp|--nis]
hostname [-b|--boot] [-F|--file filename] [hostname]
hostname [-h|--help] [-V|--version]
domainname [nisdomain] [-F file]
ypdomainname [nisdomain] [-F file]
nisdomainname [nisdomain] [-F file]
dnsdomainname
DESCRIPTION
Hostname is used to display the system's DNS name, and to display or set its hostname or NIS domain name.
GET NAME
When called without any arguments, the program displays the current names:
hostname will print the name of the system as returned by the gethostname(2) function.
domainname will print the NIS domainname of the system. domainname uses the gethostname(2) function, while ypdomainname and nisdomainname use the yp_get_default_domain(3).
dnsdomainname will print the domain part of the FQDN (Fully Qualified Domain Name). The complete FQDN of the system is returned with hostname --fqdn (but see the warnings
in section THE FQDN below).
The function gethostname(2) is used to get the hostname. When the hostname -a, -d, -f or -i is called will gethostbyname(3) be called. The difference in gethostname(2)
and gethostbyname(3) is that gethostbyname(3) is network aware, so it consults /etc/nsswitch.conf and /etc/host.conf to decide whether to read information in /etc/hostname
or /etc/hosts
SET NAME
When called with one argument or with the --file option, the commands set the host name or the NIS/YP domain name. hostname uses the sethostname(2) function, while all of
the three domainname, ypdomainname and nisdomainname use setdomainname(2). Note, that this is effective only until the next reboot. Edit /etc/hostname for permanent
change.
Note, that only the super-user can change the names.
It is not possible to set the FQDN or the DNS domain name with the dnsdomainname command (see THE FQDN below).
The host name is usually set once at system startup (normally by reading the contents of a file which contains the host name, e.g. /etc/hostname).
THE FQDN
The FQDN (Fully Qualified Domain Name) of the system is the name that the resolver(3) returns for the host name, such as, ursula.example.com. It is usually the hostname
followed by the DNS domain name (the part after the first dot). You can check the FQDN using hostname --fqdn or the domain name using dnsdomainname.
You cannot change the FQDN with hostname or dnsdomainname.
The recommended method of setting the FQDN is to make the hostname be an alias for the fully qualified name using /etc/hosts, DNS, or NIS. For example, if the hostname was
"ursula", one might have a line in /etc/hosts which reads
127.0.1.1 ursula.example.com ursula
Technically: The FQDN is the name getaddrinfo(3) returns for the host name returned by gethostname(2). The DNS domain name is the part after the first dot.
Therefore it depends on the configuration of the resolver (usually in /etc/host.conf) how you can change it. Usually the hosts file is parsed before DNS or NIS, so it is
most common to change the FQDN in /etc/hosts.
If a machine has multiple network interfaces/addresses or is used in a mobile environment, then it may either have multiple FQDNs/domain names or none at all. Therefore
avoid using hostname --fqdn, hostname --domain and dnsdomainname. hostname --ip-address is subject to the same limitations so it should be avoided as well.
OPTIONS
-a, --alias
Display the alias name of the host (if used). This option is deprecated and should not be used anymore.
-A, --all-fqdns
Displays all FQDNs of the machine. This option enumerates all configured network addresses on all configured network interfaces, and translates them to DNS domain
names. Addresses that cannot be translated (i.e. because they do not have an appropriate reverse DNS entry) are skipped. Note that different addresses may resolve to
the same name, therefore the output may contain duplicate entries. Do not make any assumptions about the order of the output.
-b, --boot
Always set a hostname; this allows the file specified by -F to be non-existant or empty, in which case the default hostname localhost will be used if none is yet
set.
-d, --domain
Display the name of the DNS domain. Don't use the command domainname to get the DNS domain name because it will show the NIS domain name and not the DNS domain
name. Use dnsdomainname instead. See the warnings in section THE FQDN above, and avoid using this option.
-f, --fqdn, --long
Display the FQDN (Fully Qualified Domain Name). A FQDN consists of a short host name and the DNS domain name. Unless you are using bind or NIS for host lookups you
can change the FQDN and the DNS domain name (which is part of the FQDN) in the /etc/hosts file. See the warnings in section THE FQDN above, and avoid using this
option; use hostname --all-fqdns instead.
-F, --file filename
Read the host name from the specified file. Comments (lines starting with a `#') are ignored.
-i, --ip-address
Display the network address(es) of the host name. Note that this works only if the host name can be resolved. Avoid using this option; use hostname --all-ip-
addresses instead.
-I, --all-ip-addresses
Display all network addresses of the host. This option enumerates all configured addresses on all network interfaces. The loopback interface and IPv6 link-local
addresses are omitted. Contrary to option -i, this option does not depend on name resolution. Do not make any assumptions about the order of the output.
-s, --short
Display the short host name. This is the host name cut at the first dot.
-V, --version
Print version information on standard output and exit successfully.
-y, --yp, --nis
Display the NIS domain name. If a parameter is given (or --file name ) then root can also set a new NIS domain.
-h, --help
Print a usage message and exit.
NOTES
The address families hostname tries when looking up the FQDN, aliases and network addresses of the host are determined by the configuration of your resolver. For instance,
on GNU Libc systems, the resolver can be instructed to try IPv6 lookups first by using the inet6 option in /etc/resolv.conf.
FILES
his file is read at boot time by the system initialization scripts to set the hostname.
/etc/hosts Usually, this is where one sets the domain name by aliasing the host name to the FQDN.
AUTHORS
Peter Tobias, <tobias@et-inf.fho-emden.de>
Bernd Eckenfels, <net-tools@lina.inka.de> (NIS and manpage).
Michael Meskes, <meskes@debian.org>
X 参考文献
本文作者:
千千寰宇
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本文链接: https://www.cnblogs.com/johnnyzen
关于博文:评论和私信会在第一时间回复,或直接私信我。
版权声明:本博客所有文章除特别声明外,均采用 BY-NC-SA 许可协议。转载请注明出处!
日常交流:大数据与软件开发-QQ交流群: 774386015 【入群二维码】参见左下角。您的支持、鼓励是博主技术写作的重要动力!