问题
Currently all the solution mentioned for getting the MAC address always use eth0.
But what if instead of eth0 my interfaces start with eth1. Also on OS X the interface names are different.
Also the interface eth0 may be present but is unused. i.e. not active, it doesn't have an IP.
So is there a way I could get the MAC address for the first available interface that is Active.(i.e. it has an inet address, I even don't want one having inet6).
For E.g
eth0 Link encap:Ethernet HWaddr <some addr>
inet6 addr: <some addr> Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:123
RX packets:123 errors:123 dropped:123 overruns:123 frame:123
TX packets:123 errors:123 dropped:123 overruns:123 carrier:123
collisions:123 txqueuelen:123
RX bytes:123 (123 MB) TX bytes:123 (123 KB)
Interrupt:123 Memory:00000000-00000000
eth1 Link encap:Ethernet HWaddr <some addr>
inet addr:<some addr> Bcast:<some addr> Mask:<some addr>
inet6 addr: <some addr> Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:123 Metric:123
RX packets:123 errors:123 dropped:123 overruns:123 frame:123
TX packets:123 errors:123 dropped:123 overruns:123 carrier:123
collisions:123 txqueuelen:123
RX bytes:123 (123 MB) TX bytes:123 (123 KB)
Interrupt:123 Memory:00000000-00000000
NOTE : I have changed the values of the output.
So in this case I want the HWaddr for eth1 and not eth0. How do I find it ? Also it should work on all the Linux flavours.
回答1:
Observe that the interface name and the MAC address are the first and last fields on a line with no leading whitespace.
If one of the indented lines contains inet addr: the latest interface name and MAC address should be printed.
ifconfig -a |
awk '/^[a-z]/ { iface=$1; mac=$NF; next }
/inet addr:/ { print iface, mac }'
Note that multiple interfaces could meet your criteria. Then, the script will print multiple lines. (You can add ; exit just before the final closing brace if you always only want to print the first match.)
回答2:
You can do as follows
ifconfig <Interface ex:eth0,eth1> | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'
Also you can get MAC for all interface as follows
cat /sys/class/net/*/address
For particular interface like for eth0
cat /sys/class/net/eth0/address
回答3:
The best Linux-specific solution is to use sysfs:
$ IFACE=eth0
$ read MAC </sys/class/net/$IFACE/address
$ echo $IFACE $MAC
eth0 00:ab:cd:12:34:56
This method is extremely clean compared to the others and spawns no additional processes since read is a builtin command for POSIX shells, including non-BASH shells. However, if you need portability to OS X, then you'll have to use ifconfig and sed methods, since OS X does not have a virtual filesystem interface like sysfs.
回答4:
$ ip route show default | awk '/default/ {print $5}'
return: eth0 (my online interface)
$ cat /sys/class/net/$(ip route show default | awk '/default/ {print $5}')/address
return: ec:a8:6b:bd:55:05 (macaddress of the eth0, my online interface)
Terminal image
回答5:
On a modern GNU/Linux system you can see the available network interfaces listing the content of /sys/class/net/, for example:
$ ls /sys/class/net/
enp0s25 lo virbr0 virbr0-nic wlp2s0
You can check if an interface is up looking at operstate in the device directory. For example, here's how you can see if enp0s25 is up:
$ cat /sys/class/net/enp0s25/operstate
up
You can then get the MAC address of that interface with:
$ cat /sys/class/net/enp0s25/address
ff:00:ff:e9:84:a5
For example, here's a simple bash script that prints MAC addresses for active interfaces:
#!/bin/bash
# getmacifup.sh: Print active NICs MAC addresses
D='/sys/class/net'
for nic in $( ls $D )
do
echo $nic
if grep -q up $D/$nic/operstate
then
echo -n ' '
cat $D/$nic/address
fi
done
And here's its output on a system with an ethernet and a wifi interface:
$ ./getmacifup.sh
enp0s25
ff:00:ff:e9:84:a5
lo
wlp2s0
For details see the Kernel documentation
Remember also that from 2015 most GNU/Linux distributions switched to systemd, and don't use ethX interface naming scheme any more - now they use a more robust naming convention based on the hardware topology, see:
- Predictable Network Interface Names
- systemd/src/udev/udev-builtin-net_id.c
回答6:
oh, if you want only the mac ether mac address, you can use that:
ifconfig | grep "ether*" | tr -d ' ' | tr -d '\t' | cut -c 6-42
(work on macintosh)
ifconfig-- get all infogrep-- keep the line with addresstr-- clean allcut-- remove the "ether" to have only the address
回答7:
Simply run:
ifconfig | grep ether | cut -d " " -f10
OR
ip a | grep ether | cut -d " " -f6
These two example commands will grep all lines with "ether" string and cut the mac address (that we need) following the number spaces (specified in the -f option) of the grepped portion.
Tested on different Linux flavors
回答8:
I know that is a little bit dated, but with basic commands, we can take the mac address of an interface:
ip link show eth0 | grep link/ether | awk '{print $2}'
Have a nice day!
回答9:
None of the above worked for me because my devices are in a balance-rr bond. Querying either would say the same MAC address with ip l l, ifconfig, or /sys/class/net/${device}/address, so one of them is correct, and one is unknown.
But this works if you haven't renamed the device (any tips on what I missed?):
udevadm info -q all --path "/sys/class/net/${device}"
And this works even if you rename it (eg. ip l set name x0 dev p4p1):
cat /proc/net/bonding/bond0
or my ugly script that makes it more parsable (untested driver/os/whatever compatibility):
awk -F ': ' '
$0 == "" && interface != "" {
printf "%s %s %s\n", interface, mac, status;
interface="";
mac=""
};
$1 == "Slave Interface" {
interface=$2
};
$1 == "Permanent HW addr" {
mac=$2
};
$1 == "MII Status" {
status=$2
};
END {
printf "%s %s %s\n", interface, mac, status
}' /proc/net/bonding/bond0
回答10:
Here's an alternative answer in case the ones listed above don't work for you. You can use the following solution(s) as well, which was found here:
ip addr
OR
ip addr show
OR
ip link
All three of these will show your MAC address(es) next to link/ether. I stumbled on this because I had just done a fresh install of Debian 9.5 from a USB stick without internet access, so I could only do a very minimal install, and received
-bash: ifconfig: command not found
when I tried some of the above solutions. I figured somebody else may come across this problem as well. Hope it helps.
回答11:
Get MAC adress for eth0:
$ cat /etc/sysconfig/network-scripts/ifcfg-eth0 | grep HWADDR | cut -c 9-25
Example:
[me@machine ~]$ cat /etc/sysconfig/network-scripts/ifcfg-eth0 | grep HWADDR | cut -c 9-25
55:b5:00:10:be:10
来源：https://stackoverflow.com/questions/23828413/get-mac-address-using-shell-script