ifconfig

Command Function

This command can be used to:

  • Query and set parameters of a network interface card (NIC), such as the IP address, network mask, gateway, and MAC address.
  • Enable or disable a NIC.

Syntax

ifconfig [option]

option:

  • [-a]
  • <interface> <address> [netmask <mask>] [gateway <address>]
  • [hw ether <address>] [mtu <size>]
  • [inet6 add <address>]
  • [inet6 del <address>]
  • [up|down]

Parameters

Table 1 Parameter description

Parameter

Description

Value Range

No parameter

Displays all NIC information, which includes the IP address, network mask, gateway, MAC address, maximum transmission unit (MTUs), and running status of each NIC.

N/A

-a

Displays data sent and received by the protocol stack.

N/A

interface

Specifies the NIC name, for example, eth0.

N/A

address

Specifies the IP address, for example, 192.168.1.10. The NIC name must be specified.

N/A

netmask

Specifies the subnet mask, for example, 255.255.255.0.

N/A

gateway

Specifies the gateway, for example, 192.168.1.1.

N/A

hw ether

Specifies the MAC address, for example, 00:11:22:33:44:55. Currently, only the ether hardware type is supported.

N/A

mtu

Specifies the MTU size, for example, 1000.
  • IPv4:

    [68,1500]

  • IPv6:

    [1280, 1500]

add

Specifies the IPv6 address, for example, 2001:a:b:c:d:e:f:d. The NIC name and inet6 must be specified.

N/A

del

Deletes an IPv6 address. You need to specify the NIC name and add the inet6 option. For details, see the example.

N/A

up

Enables the data processing function of the NIC. The NIC name must be specified.

N/A

down

Disables the data processing function of the NIC. The NIC name must be specified.

N/A

Usage

  • The ifconfig command can be used only after the TCP/IP stack is enabled.
  • Detecting an IP address conflict takes time. Each time you run the ifconfig command to set an IP address, there is a delay of about 2 seconds.

Example

  • ifconfig eth0 192.168.100.31 netmask 255.255.255.0 gateway 192.168.100.1 hw ether 00:49:cb:6c:a1:31
  • ifconfig -a
  • ifconfig eth0 inet6 add 2001:a:b:c:d:e:f:d
  • ifconfig eth0 inet6 del 2001:a:b:c:d:e:f:d

Output

  • Example 1: setting network parameters

    OHOS:/$ ifconfig eth0 192.168.100.31 netmask 255.255.255.0 gateway 192.168.100.1 hw ether 00:49:cb:6c:a1:31
OHOS:/$ ifconfig
lo      ip:127.0.0.1 netmask:255.0.0.0 gateway:127.0.0.1
        ip6: ::1/64
        HWaddr 00 MTU:0 Running Link UP
eth0    ip:192.168.100.31 netmask:255.255.255.0 gateway:192.168.100.1
        HWaddr 00:49:cb:6c:a1:31 MTU:1500 Running Default Link UP

    The following table describes the output parameters.

    Table 2 Output description

    Parameter

    Description

    ip

    IP address of the board

    netmask

    Subnet mask

    gateway

    Gateway

    HWaddr

    MAC address of the board

    MTU

    Maximum transmission unit

    Running/Stop

    Indicates whether the NIC is running.

    Default

    Indicates that the NIC is connected to the default gateway.

    Link UP/Down

    Connection status of the NIC

  • Example 2: obtaining protocol stack statistics

    OHOS # ifconfig -a
RX packets:6922  errors:0        ip dropped:4312         link dropped:67         overrun:0       bytes:0 (0.0 B)
RX packets(ip6):3     errors:0        dropped:0       overrun:0       bytes:0 (0.0 B)
TX packets:1394  errors:0        link dropped:67         overrun:0       bytes:0(0.0 B)
TX packets(ip6):3     errors:0        overrun:0       bytes:0(0.0 B)

    The following table describes the output parameters.

    Table 3 ifconfig -a output description

    Parameter

    Description

    RX packets

    Number of normal packets received at the IP layer.

    RX error

    Number of error packets received at the IP layer. The errors include the length error, verification error, IP option error, and IP header protocol error.

    RX dropped

    Number of packets discarded at the IP layer. Packets are discarded due to packet errors, packet forwarding failures, and disabled local NICs.

    RX overrun

    Number of packets that the MAC layer fails to deliver to the upper-layer protocol stack. The failure is caused by resource insufficiency at the protocol stack.

    RX bytes

    Total length of normal packets received at the IP layer, excluding the length of the fragments that are not reassembled.

    TX packets

    Number of packets that have been normally sent or forwarded at the IP layer.

    TX error

    Number of packets that the IP layer fails to send. Packets may fail to be sent because the packets cannot be routed or the packets fail to be processed in the protocol stack.

    TX dropped

    Number of packets that the MAC layer discards due to delivery failures, for example, the NIC driver fails to process the packets.

    TX overrun

    Reserved.

    TX bytes

    Total length of the packets successfully sent or forwarded at the IP layer.

  • Example 3: setting an IPv6 address

    OHOS:/$ ifconfig eth0 inet6 add 2001:a:b:c:d:e:f:d
NetifStatusCallback(eth0): nsc event: 0x8
NetifStatusCallback(eth0): nsc status changed: 0
NetifStatusCallback(eth0): nsc event: 0x200
NetifStatusCallback(eth0): nsc event: 0x8
NetifStatusCallback(eth0): nsc status changed: 1
NetifStatusCallback(eth0): nsc event: 0x200
NetifStatusCallback(eth0): nsc event: 0x200
OHOS:/$ ifconfig
lo      ip:127.0.0.1 netmask:255.0.0.0 gateway:127.0.0.1
        ip6: ::1/64
        HWaddr 00 MTU:0 Running Link UP
eth0    ip:192.168.1.10 netmask:255.255.255.0 gateway:192.168.1.1
        ip6: 2001:A:B:C:D:E:F:D/64
        HWaddr 66:2f:e5:bd:24:e6 MTU:1500 Running Default Link UP

  • Example 4: deleting an IPv6 address

    OHOS:/$ ifconfig eth0 inet6 del 2001:a:b:c:d:e:f:d
NetifStatusCallback(eth0): nsc event: 0x200
OHOS:/$ ifconfig
lo      ip:127.0.0.1 netmask:255.0.0.0 gateway:127.0.0.1
        ip6: ::1/64
        HWaddr 00 MTU:0 Running Link UP
eth0    ip:192.168.1.10 netmask:255.255.255.0 gateway:192.168.1.1
        HWaddr 66:2f:e5:bd:24:e6 MTU:1500 Running Default Link UP