linux IP地址设置大全（各系统全）

https://www.linode.com/docs/networking/linux-static-ip-configuration

Linux Static IP Configuration

Updated Tuesday, August 12, 2014 by Linode

By default, Linodes use DHCP to acquire their IP address, routing and DNS information. However, DHCP will only assign one IP to your Linode, so if you have multiple IPs, you’ll need to use a static configuration. Even if you only have one IP, you can still do a static assignment, but it’s not required in most cases.

As errors in network configurations may cause SSH connections to be disconnected, it is advised that you use the Linode Shell (LISH) when making network configuration changes. See [Using the Linode Shell (LISH)] (/docs/networking/using-the-linode-shell-lish) for more information.

Some distributions will determine the netmask based on the block of the IP address. The blocks of each type of IP address are:

• Public IPv4 - /24
• Private IPv4 - /17
• IPv6 - /64 (unless you have another pool assigned to you, you can see this from the “Remote Access” tab of the Linode Manager)

Obtain Network Configuration

Before you edit any files, you’ll need to obtain some information. Log into the [Linode Manager] (https://manager.linode.com/) and click the “Remote Access” tab. You’ll find your IP addresses (both public and private, if you have a private IP assigned), gateways, netmasks and DNS resolvers.

Keep this information handy, because you’ll need to refer to it as you configure your Linode’s network settings. Since Linodes only have one virtual ethernet interface (eth0), you’ll need to assign additional IPs to aliases on that interface. This means you’ll append a colon and a number to the interface name. For these examples, the aliases are numbered in the order they were given, but most outbound connections will originate from the IP assigned to the eth0 interface. If you need server daemons to bind to a particular IP address, you’ll need to specify the correct IP in their configuration files.

Please note that although your VPS may have multiple IP addresses assigned to it, you should only specify a default gateway for one IP. This gateway should be the one that corresponds to the IP address you are setting it on. For example, if you are setting the default gateway for “12.34.56.78” you should use “12.34.56.1” for the gateway.

A default gateway should not be specified for private IP addresses. Additionally, the subnet mask for private IP addresses should be set to “255.255.128.0” (not “255.255.255.0”).

Hostname and FQDN Settings

If you haven’t already done so, set your system’s hostname and FQDN (fully qualified domain name). Your hostname should be something unique; some people name their systems after planets, others after philosophers, etc. Please note that the system’s hostname has no relationship to websites or email services hosted on it, aside from providing a name for the system itself. Thus, your hostname should not be “www” or anything else too generic.

Debian and Ubuntu

Issue the following commands to set the hostname, replacing “plato” with the hostname of your choice:

1 2	echo "plato" > /etc/hostname hostname -F /etc/hostname

If it exists, edit the file /etc/default/dhcpd to comment out the “SET_HOSTNAME” directive:

/etc/default/dhcpcd

1	#SET_HOSTNAME='yes'

Proceed to the section entitled “Update /etc/hosts” to continue.

CentOS/Fedora

Issue the following commands to set the hostname, replacing “plato” with the hostname of your choice:

1 2	echo "HOSTNAME=plato" >> /etc/sysconfig/network hostname "plato"

Proceed to the section entitled “Update /etc/hosts” to continue.

Slackware

Issue the following commands to set the hostname, replacing “plato” with the hostname of your choice:

1 2	echo "plato" > /etc/HOSTNAME hostname -F /etc/HOSTNAME

Proceed to the section entitled “Update /etc/hosts” to continue.

Gentoo

Issue the following commands to set the hostname, replacing “plato” with the hostname of your choice:

1 2	echo "HOSTNAME=\"plato\"" > /etc/conf.d/hostname /etc/init.d/hostname restart

Proceed to the section entitled “Update /etc/hosts” to continue.

Arch Linux

Issue the following commands to set the hostname, replacing “plato” with the hostname of your choice:

1 2	echo "plato" > /etc/hostname hostname -F /etc/hostname

Proceed to the section entitled “Update /etc/hosts” to continue.

Update /etc/hosts

Next, edit your /etc/hosts file to resemble the following example, replacing “plato” with your chosen hostname, “example.com” with your system’s domain name, and “12.34.56.78” with your system’s IP address. As with the hostname, the domain name part of your FQDN does not necessarily need to have any relationship to websites or other services hosted on the server (although it may if you wish). As an example, you might host “www.something.com” on your server, but the system’s FQDN might be “mars.something.com.”

/etc/hosts

1 2	127.0.0.1 localhost.localdomain localhost 12.34.56.78 plato.example.com plato

The value you assign as your system’s FQDN should have an “A” record in DNS pointing to your Linode’s IP address. For more information on configuring DNS, please see our guide on [configuring DNS with the Linode Manager] (/library/dns-guides/configuring-dns-with-the-linode-manager).

DNS Resolver Settings

If you’ve migrated to a new location, you may need to edit your /etc/resolv.conf file so that your Linode can resolve DNS queries. Your nameservers are listed under the “Remote Access” tab. Thesearch and domain lines are optional, but you should definitely include the options rotate line.

In the example below, change the IP addresses to reflect the values shown under the “Remote Access” tab of the Linode Manager.

/etc/resolv.conf

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domain members.linode.com search members.linode.com nameserver 96.76.54.32 nameserver 76.54.32.10 options rotate

Static IP Configuration

Debian & Ubuntu

Since Ubuntu is based on Debian, their configuration is the same. The relevant file to edit is/etc/network/interfaces - the file syntax is fairly straightforward, but you can read the comments in the file for more details about what each line does.

In the example below, change the IP addresses to reflect the values shown under the “Remote Access” tab of the Linode Manager.

/etc/network/interfaces

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# The loopback interface auto lo iface lo inet loopback # Configuration for eth0 # This line ensures that the interface will be brought up during boot auto eth0 eth0:0 eth0:1 # The address and gateway are necessary. # The netmask is taken automatically from the block. # Example: /24 is considered to be a public IP address: netmask 255.255.255.0 iface eth0 inet static address 12.34.56.78/24 gateway 12.34.56.1 # This is a second public IP address iface eth0:0 inet static address 34.56.78.90/24 # This is a private IP address. Private IPs do not have a gateway (they are not publicly routable). # All you need to specify is the address and the block. The netmask is taken from the block. # Example: /17 is considered to be a private IP address: netmask 255.255.128.0 iface eth0:1 inet static address 192.168.133.234/17

Restart networking:

1	ifdown -a && ifup -a

From the Linode, ping each of the default gateways listed on the “Remote Access” tab of the Linode Manager:

1 2	ping 12.34.56.1 ping 98.76.54.1

CentOS 7 & Fedora 20

Note: CentOS 7/Fedora 20 no longer uses the network service. Instead, use the nmcli utility. The Network Manager in CentOS 7 also allows you to have each IP address defined in one interface file.

In the example below, change the IP addresses to reflect the values shown under the “Remote Access” tab of the Linode Manager.

You must create the /etc/sysconfig/network-scripts/ifcfg-static-eth0 file.

/etc/sysconfig/network-scripts/ifcfg-static-eth0

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# Configuration for eth0 DEVICE=eth0 BOOTPROTO=none ONBOOT=yes # Adding a public IP address. # The netmask is taken from the PREFIX (where 24 is Public IP, 17 is Private IP) IPADDR0=12.34.56.78 PREFIX0=24 # Specifying the gateway GATEWAY0=12.34.56.1 # Adding a second public IP address. IPADDR1=34.56.78.90 PREFIX1=24 # Adding a private IP address. IPADDR2=192.168.133.234 PREFIX2=17

Reload NetworkManager:

1	nmcli con reload

Put the DHCP network configuration offline:

1	nmcli con down "Wired connection 1"

Bring the static network configuration we just created online:

1	nmcli con up "System static-eth0"

Any changes you make to the configuration will require you to reload and down/up the interface.

From the Linode, ping each of the default gateways listed on the “Remote Access” tab of the Linode Manager:

1 2	ping 12.34.56.1 ping 98.76.54.1

CentOS 6.5

CentOS 6.5 keeps the information for each interface in a separate file named/etc/sysconfig/network-scripts/ifcfg-<interface_alias_name> so you’ll need to create one for eth0 and one for each alias.

In the example below, change the IP addresses to reflect the values shown under the “Remote Access” tab of the Linode Manager.

/etc/sysconfig/network-scripts/ifcfg-eth0

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# Configuration for eth0 DEVICE=eth0 BOOTPROTO=none # This line ensures that the interface will be brought up during boot. ONBOOT=yes # eth0 - This is the main IP address that will be used for most outbound connections. # The address, netmask, and gateway are all necessary. IPADDR=12.34.56.78 NETMASK=255.255.255.0 GATEWAY=12.34.56.1

/etc/sysconfig/network-scripts/ifcfg-eth0:0

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# Configuration for eth0:0 DEVICE=eth0:0 BOOTPROTO=none # This line ensures that the interface will be brought up during boot. ONBOOT=yes # eth0:0 IPADDR=34.56.78.90 NETMASK=255.255.255.0

/etc/sysconfig/network-scripts/ifcfg-eth0:1

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# Configuration for eth0:1 DEVICE=eth0:1 BOOTPROTO=none # This line ensures that the interface will be brought up during boot. ONBOOT=yes # eth0:1 # This is a private IP address. Private IPs do not have a gateway (they are not publicly routable). # All you need to specify is the address and netmask IPADDR=192.168.133.234 NETMASK=255.255.128.0

Restart networking:

1	service network restart

From the Linode, ping each of the default gateways listed on the “Remote Access” tab of the Linode Manager:

1 2	ping 12.34.56.1 ping 98.76.54.1

Gentoo

Networking in Gentoo utilizes the netifrc utility.

You will need to edit the /etc/conf.d/net file so that it resembles the example below. However, you should change the IP addresses in the example to match the IP addresses from the “Remote Access” tab of the Linode Manager.

{. file: }

/etc/conf.d/net

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# Configuration for eth0 on multiple IP addresses # Each IP address is separated by a space config_eth0="12.34.56.78/24 34.56.78.90/24 192.168.133.234/17 1234:5678:9abc:def::1/64" routes_eth0="default gw 12.34.56.1"

Restart networking interface:

1	/etc/init.d/net.eth0 restart

From the Linode, ping each of the default gateways listed on the “Remote Access” tab of the Linode Manager:

1 2	ping 12.34.56.1 ping 98.76.54.1

Arch Linux

Networking on Arch Linux is configured using the systemd-networkd service.

The configuration file for systemd-networkd should be created in /etc/systemd/network.

Note: The systemd version may be outdated, and you may need to run pacman -Syu before continuing. You can check the version by running systemctl --version.

1. Prior to creating the configuration file, you will need to use LISH to disable the DHCP connection that we provide by default. To do so, on LISH, use the following command:

   ln -s /dev/null /etc/systemd/network/10-dhcp.network

2. Create the /etc/systemd/network/50-static.network file so that it resembles the example below. Be sure to change the IP addresses to reflect the values shown under the “Remote Access” tab of the Linode Manager.

   /etc/systemd/network/50-static.network

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   [Match] Name=eth0 [Network] Address=12.34.56.78/24 Address=34.56.78.90/24 Address=192.168.133.234/17 Gateway=12.34.56.1

3. Restart systemd-networkd. To do so, run this command:

   systemctl restart systemd-networkd

Once you have made these changes, ping each of the default gateways listed on the “Remote Access” tab of the Linode Manager:

1 2	ping 12.34.56.1 ping 98.76.54.1

OpenSUSE

In the example below, change the IP addresses to reflect the values shown under the “Remote Access” tab of the Linode Manager.

/etc/sysconfig/network/ifcfg-eth0

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# Configuration for eth0 BOOTPROTO='static' # This line ensures that the interface will be brought up during boot. STARTMODE='onboot' # eth0 - This is the main IP address that will be used for most outbound connections # The address, netmask and gateway are all necessary. The metric is not necessary, but # ensures you always talk to the same gateway if you have multiple public IPs from # different subnets. IPADDR='12.34.56.78' NETMASK='255.255.255.0' # eth0:0 # This is a second public IP address. IPADDR1='34.56.78.90' NETMASK1='255.255.255.0' LABEL1='0' # eth0:1 - Private IP # Private IP addresses do not have a gateway. IPADDR2='192.168.133.234' NETMASK2='255.255.128.0' LABEL2='1'

Create the following file if necessary. You will need to change the gateway (0.0.0.0) to your gateway found in the “Remote Access” tab of the Linode Manager:

/etc/sysconfig/network/routes

1 2	# Destination Gateway Netmask Device default 0.0.0.0 255.255.255.0 eth0

Double-check that your /etc/resolv.conf exists and is correct.

Restart networking:

1	systemctl reload network

From the Linode, ping each of the default gateways listed in the “Remote Access” tab of the Linode Manager. ::

1 2	ping 12.34.56.1 ping 98.76.54.1

This guide is published under a CC BY-ND 3.0 license.