在ArchLinux的arm版本上设置固定IP

2019-11-01 遇到的一点小问题
最近在树莓派上做东西，有几张SD卡需要来回切换。使用ssh经常遇到IP变掉的事。
系统是通过Systemd-networkd来进行IP管理的。

[root@alarmpi ~]# systemctl status systemd-networkd
* systemd-networkd.service - Network Service
   Loaded: loaded (/usr/lib/systemd/system/systemd-networkd.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2019-09-23 23:54:29 UTC; 1 months 10 days ago
     Docs: man:systemd-networkd.service(8)
 Main PID: 225 (systemd-network)
   Status: "Processing requests..."
    Tasks: 1
   Memory: 2.1M
   CGroup: /system.slice/systemd-networkd.service
           `-225 /usr/lib/systemd/systemd-networkd

Sep 23 23:54:28 alarmpi systemd[1]: Starting Network Service...
Sep 23 23:54:29 alarmpi systemd-networkd[225]: Enumeration completed
Sep 23 23:54:29 alarmpi systemd[1]: Started Network Service.
Sep 23 23:54:29 alarmpi systemd-networkd[225]: eth0: IPv6 successfully enabled
Nov 01 10:17:11 alarmpi systemd-networkd[225]: eth0: Gained carrier
Nov 01 10:17:12 alarmpi systemd-networkd[225]: eth0: DHCPv4 address 192.168.10.218/22 via 192.168.8.1
Nov 04 01:08:10 alarmpi systemd-networkd[225]: eth0: Gained IPv6LL
Nov 04 01:08:22 alarmpi systemd-networkd[225]: eth0: Configured

因为半年前做的功能是通过修改dhcpcd的配置文件/etc/dhcpcd.conf，重启服务systemctl restart dhcpcd，重启网卡ip link set eth0 down和ip link set eth0 up来进行设备的动态IP和静态IP设置管理。
所以继续通过修改DHCP配置文件 /etc/dhcpcd.conf来设置固定IP：

interface eth0
static ip_address=192.168.10.250/22
static routers=192.168.8.1
static domain_name_servers=218.85.152.99

在文件后面添加上面内容，命令systemctl start dhcpcd启动dhcpcd服务就可以正常设置静态IP了，需要动态IP只需要删掉添加的内容就行。
使用ip addr看会有两个IP，命令systemctl disable systemd-networkd和systemctl enable dhcpcd设定开机启动项。重启就可以了。

[root@alarmpi tmp]# systemctl disable systemd-networkd
Removed /etc/systemd/system/multi-user.target.wants/systemd-networkd.service.
Removed /etc/systemd/system/network-online.target.wants/systemd-networkd-wait-online.service.
Removed /etc/systemd/system/dbus-org.freedesktop.network1.service.
Removed /etc/systemd/system/sockets.target.wants/systemd-networkd.socket.

/etc/dhcpcd.conf