Config Wired Connection On Arch Linux

Short answer: Run sudo dhcpcd.

Original Investigating Article

I was in a cafe called XiangRiKui, where is weird that without wireless network. If you want to connect to the Internet, they will provide you a Ethernet cable. This time, I only took my EPC with Arch Linux installed. And I didn't config any wired connection.

Xiangrikui Cafe

I had to connect to internet with my iPhone's personal hotspot, and open Arch Linux's guide page[1]. And here is the instructions:

$ ip link

The output was:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN mode DEFAULT 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp1s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT qlen 1000
    link/ether bc:ae:c6:3e:b3:70 brd ff:ff:ff:ff:ff:ff
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DORMANT qlen 1000
    link/ether 46:5e:a0:b3:d4:ec brd ff:ff:ff:ff:ff:ff

The interface enp1s0 should be wired interface, since Ethernet interfaces are begin with a letter e. If we're unsure, try:

$ iwconfig

The output was:

wlan0     IEEE 802.11bgn  ESSID:"mitnk's iPhone"  
      Mode:Managed  Frequency:2.417 GHz  Access Point: EE:7D:28:E3:E1:88   
      Bit Rate=6 Mb/s   Tx-Power=19 dBm   
      Retry  long limit:7   RTS thr:off   Fragment thr:off
      Power Management:off
      Link Quality=65/70  Signal level=-45 dBm  
      Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
      Tx excessive retries:5  Invalid misc:17   Missed beacon:0

lo        no wireless extensions.

enp1s0    no wireless extensions.

This indicated that lo and enp1s0 is NOT wireless interfaces.

Now we activate this interface:

$ sudo ip link set enp1s0 up

Genericly, we need to know Subnet mask, Gateway's IP address, etc. But we can use dhcpcd do this for us. Just type:

$ sudo dhcpcd

To check, run command ifconfig, if you can see something like inet under enp1s0, the wired connection was done successfully.

[1] Arch Linux Beginners' Guide