白白胖胖

关于Linux中网络连接配置(NetworkManager)的一些笔记

常见的配置网络方法：

通过nmcli connection add命令配置，会自动生成ifcfg文件。

手动配置ifcfg-name文件，通过nmcli connection reload来加载生效。

手动配置ifcfg-name文件，通过旧服务network.service来加载生效。

通过nmtui 以图形化的方式配置

基于NetworkManager的系统守护进程，主要负责管理网络接口(device)和连接配置(connection)。它监视和管理网络设置，并使用/etc/sysconfig/networkscripts/目录中的文件来存储它们。

在NetworkManager中,设备是网络接口。连接是可以为设备配置的设置的集合。任何设备在同一时间只有一个连接是活动的。可能存在多个连接，用于不同设备的使用，或者允许对同一设备的配置进行更改。

每个连接都有一个名称或ID来标识它。/etc/sysconfig/network-scripts/ifcfg-name文件存储连接的持久配置，其中name是连接的名称。当连接名中有空格时，文件名中的空格将被替换为下划线。如果需要，这个文件可以手工编辑。

nmcli程序从shell提示符创建和编辑连接文件。

查看组网信息，可以通过nmcli dev status命令用来查看所有网络设备的当前状态。
┌──[root@liruilongs.github.io]-[~]
└─$nmcli dev status
DEVICE      TYPE      STATE      CONNECTION
privbr0     bridge    connected  privbr0
virbr0      bridge    connected  virbr0
eth0        ethernet  connected  eth0
vnet0       tun       connected  vnet0
vnet1       tun       connected  vnet1
lo          loopback  unmanaged  --
virbr0-nic  tun       unmanaged  --

当然nmcli操作除dev和con之外其他一些对象，暂时不清楚是干什么的，以后有机会研究下。
┌──[root@liruilongs.github.io]-[~]
└─$nmcli
agent       connection  device      general     help        monitor     networking  radio

nmcli con show命令用来显示所有连接的列表。添加--active选项来只列出活动的连接。
┌──[root@liruilongs.github.io]-[~]
└─$nmcli con show --active
NAME     UUID                                  TYPE      DEVICE
privbr0  ef4e7961-d070-920c-71d7-51d86377d921  bridge    privbr0
virbr0   667e5abb-da79-4c74-b4d6-dc203a14948c  bridge    virbr0
eth0     5fb06bd0-0bb0-7ffb-45f1-d6edd65f3e03  ethernet  eth0
vnet0    d801c759-2775-4a4c-8694-85adb30af9db  tun       vnet0
vnet1    a33cf39d-c485-40d3-affd-6fed087fbbe8  tun       vnet1

device

device即网卡设备。常用的命令如下
┌──[root@servera.lab.example.com]-[~]
└─$nmcli device
connect     disconnect  lldp        monitor     set         status
delete      help        modify      reapply     show        wifi

关于device，一般不怎么操作，通过show命令 nmcli device show eth0可以查看网卡详细信息
┌──[root@servera.lab.example.com]-[~]
└─$nmcli device show eth0
GENERAL.DEVICE:                         eth0
GENERAL.TYPE:                           ethernet
GENERAL.HWADDR:                         52:54:00:00:FA:0A
GENERAL.MTU:                            1500
GENERAL.STATE:                          100 (connected)
GENERAL.CONNECTION:                     Wired connection 1
GENERAL.CON-PATH:                       /org/freedesktop/NetworkManager/ActiveConnection/1
WIRED-PROPERTIES.CARRIER:               on
IP4.ADDRESS[1]:                         172.25.250.10/24
IP4.GATEWAY:                            172.25.250.254
IP4.ROUTE[1]:                           dst = 172.25.250.0/24, nh = 0.0.0.0, mt = 100
IP4.ROUTE[2]:                           dst = 0.0.0.0/0, nh = 172.25.250.254, mt = 100
IP4.DNS[1]:                             172.25.250.254
IP6.ADDRESS[1]:                         fe80::984:87d2:dba7:1007/64
IP6.GATEWAY:                            --
IP6.ROUTE[1]:                           dst = fe80::/64, nh = ::, mt = 100
IP6.ROUTE[2]:                           dst = ff00::/8, nh = ::, mt = 256, table=255

connection

connection 即为添加动态网络连接配置，常用的命令如下
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection
add      delete   edit     help     load     monitor  show
clone    down     export   import   modify   reload   up

查看show

通过nmcli connection show可以查看网络配置的详细信息
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection show
NAME                UUID                                  TYPE      DEVICE
Wired connection 1  4ae4bb9e-8f2d-3774-95f8-868d74edcc3c  ethernet  eth0
Wired connection 2  c0e6d328-fcb8-3715-8d82-f8c37cb42152  ethernet  --
Wired connection 3  9b5ac87b-572c-3632-b8a2-ca242f22733d  ethernet  --

添加add

通过 nmcli connection add 添加一个网络连接,默认IP为动态获取
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection add type ethernet con-name dynamic-eth1 ifname eth1
Connection 'dynamic-eth1' (91575fc2-a151-4da4-a174-757b4bf9c483) successfully added.

这里添加的网络配置名字为dynamic-eth1，使用的网卡为eth1,查看添加的网络连接配置
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection show
NAME                UUID                                  TYPE      DEVICE
Wired connection 2  c0e6d328-fcb8-3715-8d82-f8c37cb42152  ethernet  eth1
Wired connection 3  9b5ac87b-572c-3632-b8a2-ca242f22733d  ethernet  eth2
Wired connection 1  4ae4bb9e-8f2d-3774-95f8-868d74edcc3c  ethernet  eth0
dynamic-eth1        91575fc2-a151-4da4-a174-757b4bf9c483  ethernet  --

这里IP地址获取方式默认为动态获取
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection show  dynamic-eth1 | grep ipv4.m
ipv4.method:                            auto
ipv4.may-fail:                          yes

添加一个连接，网络类型配置为因特网(ethernet)
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection add con-name static ifname eth1 type ethernet
Connection 'static' (1833628a-ebe3-4fd0-9be1-9bed877067c9) successfully added.

修改modify

nmcli con mod name命令用于修改连接设置。这些更改也保存在连接的/etc/sysconfig/network-scripts/ifcfg-name文件中。
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection modify static  +ipv4.dns 114.114.114.114
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection show static | grep ipv4.dn
ipv4.dns:                               172.25.25.254,114.114.114.114
ipv4.dns-search:                        --
ipv4.dns-options:                       --
ipv4.dns-priority:                      0

修改ipv4的IP地址获取方式为手动，并指定IP地址、网关、DNS
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection modify static ipv4.method  manual ipv4.addresses  172.25.25.10/24 ipv4.gateway 172.25.25.254 ipv4.dns 172.25.25.254

查看系修改后的信息，切记修改完需要从新激活
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection show static | grep ipv4
ipv4.method:                            manual
ipv4.dns:                               172.25.25.254
ipv4.dns-search:                        --
ipv4.dns-options:                       --
ipv4.dns-priority:                      0
ipv4.addresses:                         172.25.25.10/24
ipv4.gateway:                           172.25.25.254
ipv4.routes:                            --
ipv4.route-metric:                      -1
ipv4.route-table:                       0 (unspec)
ipv4.routing-rules:                     --
ipv4.ignore-auto-routes:                no
ipv4.ignore-auto-dns:                   no
ipv4.dhcp-client-id:                    --
ipv4.dhcp-timeout:                      0 (default)
ipv4.dhcp-send-hostname:                yes
ipv4.dhcp-hostname:                     --
ipv4.dhcp-fqdn:                         --
ipv4.never-default:                     no
ipv4.may-fail:                          yes
ipv4.dad-timeout:                       -1 (default)

激活up

nmcli con up name命令用来激活绑定了名称连接的网络接口。该命令使用连接名，而不是网络接口名,下面执行可以动态获取ip
┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection up static
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/288)

断开disconnect

nmcli dev disconnect device命令用来断开设备的网络接口，使其断开。命令缩写为nmcli dev dis device
┌──[root@servera.lab.example.com]-[~]
└─$nmcli dev dis dynamic-eth1
这里需要说明的是，nmcli con down name命令通常不是禁用网络接口的最佳方法，因为它会导致连接中断。然而，默认情况下，大多数有线系统连接配置为启用自动连接。这将在网络接口可用时立即激活连接。因为连接的网络接口仍然是可用的，nmcli con down name会将该接口关闭，但随后NetworkManager会立即将其打开，除非该连接与该接口完全断开。

删除delete

┌──[root@servera.lab.example.com]-[~]
└─$nmcli connection delete dynamic-eth1
Connection 'dynamic-eth1' (91575fc2-a151-4da4-a174-757b4bf9c483) successfully deleted.

配置文件

网络连接配置中，静态连接属性保存在/etc/sysconfig/network-scripts/ifcfg-*配置文件中。

动态的连接数据，如设置IP自动获取，即从DHCP服务器获得的，是不持久存储的。

执行nmcli con show name命令查询连接的当前设置。小写设置是可以更改的静态属性。大写设置是连接实例临时使用的动态设置。
┌──[root@liruilongs.github.io]-[~]
└─$nmcli con show vnet0
connection.id:                          vnet0
connection.uuid:                        d801c759-2775-4a4c-8694-85adb30af9db
connection.stable-id:                   --
connection.type:                        tun
connection.interface-name:              vnet0
...................
GENERAL.NAME:                           vnet0
GENERAL.UUID:                           d801c759-2775-4a4c-8694-85adb30af9db
GENERAL.DEVICES:                        vnet0
GENERAL.IP-IFACE:                       vnet0
GENERAL.STATE:                          activated
......

配置文件信息查看

┌──[root@servera.lab.example.com]-[~]
└─$cd /etc/sysconfig/network-scripts/
┌──[root@servera.lab.example.com]-[/etc/sysconfig/network-scripts]
└─$cat ifcfg-static
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=none
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=no
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=static
UUID=1833628a-ebe3-4fd0-9be1-9bed877067c9
DEVICE=eth1
ONBOOT=yes
IPADDR=172.25.25.10
PREFIX=24
GATEWAY=172.25.25.254
DNS1=172.25.25.254
IPV6_DISABLED=yes
DNS2=114.114.114.114

配置文件修改后需要从新加载激活

┌──[root@servera.lab.example.com]-[/etc/sysconfig/network-scripts]
└─$nmcli connection reload
┌──[root@servera.lab.example.com]-[/etc/sysconfig/network-scripts]
└─$nmcli connection up static
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/290)

谁可以修改网络设置

修改网络配置的权限：root和以及本地登录的普通用户可以修改，通过SSH远程的普通用户没有权限
ROOT
┌──[root@liruilongs.github.io]-[~]
└─$nmcli general permissions
PERMISSION                                                        VALUE
org.freedesktop.NetworkManager.enable-disable-network             yes
org.freedesktop.NetworkManager.enable-disable-wifi                yes
org.freedesktop.NetworkManager.enable-disable-wwan                yes
org.freedesktop.NetworkManager.enable-disable-wimax               yes
org.freedesktop.NetworkManager.sleep-wake                         yes
org.freedesktop.NetworkManager.network-control                    yes
org.freedesktop.NetworkManager.wifi.share.protected               yes
org.freedesktop.NetworkManager.wifi.share.open                    yes
org.freedesktop.NetworkManager.settings.modify.system             yes
org.freedesktop.NetworkManager.settings.modify.own                yes
org.freedesktop.NetworkManager.settings.modify.hostname           yes
org.freedesktop.NetworkManager.settings.modify.global-dns         yes
org.freedesktop.NetworkManager.reload                             yes
org.freedesktop.NetworkManager.checkpoint-rollback                yes
org.freedesktop.NetworkManager.enable-disable-statistics          yes
org.freedesktop.NetworkManager.enable-disable-connectivity-check  yes
org.freedesktop.NetworkManager.wifi.scan                          unknown

本地登录的普通用户

远程登录的普通用户

[liruilong@liruilongs /]$nmcli general permissions
PERMISSION                                                        VALUE
org.freedesktop.NetworkManager.enable-disable-network             no
org.freedesktop.NetworkManager.enable-disable-wifi                no
org.freedesktop.NetworkManager.enable-disable-wwan                no
org.freedesktop.NetworkManager.enable-disable-wimax               no
org.freedesktop.NetworkManager.sleep-wake                         no
org.freedesktop.NetworkManager.network-control                    auth
org.freedesktop.NetworkManager.wifi.share.protected               no
org.freedesktop.NetworkManager.wifi.share.open                    no
org.freedesktop.NetworkManager.settings.modify.system             auth
org.freedesktop.NetworkManager.settings.modify.own                auth
org.freedesktop.NetworkManager.settings.modify.hostname           auth
org.freedesktop.NetworkManager.settings.modify.global-dns         auth
org.freedesktop.NetworkManager.reload                             auth
org.freedesktop.NetworkManager.checkpoint-rollback                auth
org.freedesktop.NetworkManager.enable-disable-statistics          no
org.freedesktop.NetworkManager.enable-disable-connectivity-check  no
org.freedesktop.NetworkManager.wifi.scan                          unknown