linux - 提取节点 IP 而不解析 ifconfig 的输出

Question

ifconfig 在我的机器上的输出如下:

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
    ether 3c:a8:2a:22:64:dc  txqueuelen 1000  (Ethernet)
    RX packets 7574600  bytes 945219457 (901.4 MiB)
    RX errors 0  dropped 10  overruns 0  frame 0
    TX packets 0  bytes 0 (0.0 B)
    TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
    device interrupt 16

eth1: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 3c:a8:2a:22:64:dd  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 17

eth2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.25.26.78  netmask 255.255.254.0  broadcast 10.25.27.255
        inet6 fe80::8edc:d4ff:feab:48a0  prefixlen 64  scopeid 0x20<link>
        ether 8c:dc:d4:ab:48:a0  txqueuelen 1000  (Ethernet)
        RX packets 1459110828  bytes 2115198897739 (1.9 TiB)
        RX errors 0  dropped 32460  overruns 0  frame 0
        TX packets 1527389441  bytes 2229468090451 (2.0 TiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eth3: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 3c:a8:2a:22:64:de  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 16

eth4: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 3c:a8:2a:22:64:df  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 17

eth5: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 8c:dc:d4:ab:48:a1  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eth6: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 8c:dc:d4:a8:a0:e8  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eth7: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether 8c:dc:d4:a8:a0:e9  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1  (Local Loopback)
        RX packets 77128853  bytes 11309319030 (10.5 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 77128853  bytes 11309319030 (10.5 GiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

因为我想从eth2中提取IP(不同的节点也可以在eth2、eth5等中有IP)。总而言之，我将 IP 提取为:

/sbin/ifconfig|grep 'inet addr'|grep -v '127.0.0.1'|head -1|awk '{print $2}'|awk -F':' '{print $2}'

不过，我得到的输出是空字符串。我哪里出错了？

我想提取 ip，我们提供了 inet 和网络掩码并且 inet 不应该是 127.0.0.1。

Answer 1

首先，如果您不想解析 ifconfig 的输出，您可以使用

hostname -i

它将提供分配给您的主机名的 IP 地址。

如果你想解析上面的输出并只查找 IPv4 地址，你可以试试这个:

cat test.txt |grep 'inet'|grep -v '127.0.0.1' | awk '{ print $2 }' | grep -oE "\b((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b"