I'm wondering how I can query by IP address using sed, and it will show which interface name that is using it.
For example..
ipconfig -a | grep 10.0.0.10
I would expect it to come back with ETH0
ifconfig | grep -B1 10.0.0.10 | grep -o "^\w*"
You should use this comand :
ifconfig | grep -B1 "inet addr:10.0.0.10" | awk '$1!="inet" && $1!="--" {print $1}'
Hope this help !
ip -br -4 a sh | grep 10.0.0.10 | awk '{print $1}'
If you want sed specific solution you may try this. Its little hard to digest how it works , but finally this combination works.
ifconfig | sed -n '/addr:10.0.0.10/{g;H;p};H;x' | awk '{print $1}'
If you want to take it as an argument via script use "$1" or so instead if 10.0.0.10.
Sed manual for reference : http://www.gnu.org/software/sed/manual/sed.html#tail
Related
ipconfig does not exist anymore as a command available in Ubuntu 20.04 and later I assume. The new command is just ip. When I run the ip address command I get the entire list of all devices and ip addresses associated. I want just the eth0 device and public ip 4 address associated.
I want just the bare ip address octets only. I want this to work on both Linux and Mac OS.
I found this pipe of cut and sed to work fine to get what I want:
on linux:
ip a | grep eth0 | cut -d " " --fields=6 | sed '2q;d' | awk -F'/' '{print $1}'
on BSD / Darwin / Mac OS:
ip a | grep en0 | tr -s 'inet' ' ' | sed '2q;d' | tr -s '' | awk -F' *? *' '{print $2}' | awk -F '/' '{print $1}'
which results in just the bare ip address I needed. I had to do some trial and error on what field column I actual needed. This probably could be more generalized, but this works for my use case.
Added a public git to just curl and run from anywhere like:
curl -L https://cutt.ly/UUYcT1r | /bin/bash
ifconfig | grep -m1 "inet addr"
Gives me
inet addr:172.30.1.6 Bcast:172.30.140.255 Mask:255.255.252.0
However, I only want the ip, which is 172.30.1.6. How can I do this?
Note that I have to be using ifconfig, as this is an embedded system with limited functionalities.
Get out your scissors, it's cuttin' time.
echo inet addr:172.30.1.6 Bcast:172.30.140.255 Mask:255.255.252.0 | cut -d : -f 2 | cut -d " " -f 1
One way to do it ..
ifconfig | grep -m1 "inet addr" | awk '{print $2}' | awk -F: '{print $2}'
If all you want to do is obtain the ip address, there might be easier ways of achieving that using say hostname -i ( reference Which terminal command to get just IP address and nothing else? )
Since others have mentioned cut and awk, I will provide a solution using sed :
echo "inet addr:172.30.1.6 Bcast:172.30.140.255 Mask:255.255.252.0" | sed -e "s/.*\(addr:[^ ]*\) .*/\1/"
addr:172.30.1.6
echo "inet addr:172.30.1.6 Bcast:172.30.140.255 Mask:255.255.252.0" | sed -e "s/.*addr:\([^ ]*\) .*/\1/"
172.30.1.6
Use cut with a delimiter
| cut -d':' -f 2 | cut -d' ' -f 1
Is this all you're trying to do?
awk -F'[: ]' '/inet addr/{print $3; exit}'
For example using cat file in place of ifconfig:
$ cat file
inet addr:172.30.1.6 Bcast:172.30.140.255 Mask:255.255.252.0
$ cat file | awk -F'[: ]' '/inet addr/{print $3; exit}'
172.30.1.6
Here's a way to do it with a single sed command, eliminating the call to grep:
ifconfig | sed -n '/inet addr/{s/^.*inet addr:\([^ ]*\).*$/\1/p;q}'
There are a few things going on here:
sed -n tells sed not to print every line like it normally does
/inet addr/ is a sed address - it tells sed to only operate on lines containing "inet addr"
The { and } brackets define a block of commands to be run, with the commands separated by a ;
The s command is fairly straightforward - it just captures the IP and replaces the whole line with just the IP
The p flag at the end of the s command tells sed to print the result of the substitution. This is necessary because we called sed with the -n option.
The q command tells sed to quit, so that it only processes the first line containing "inet addr".
Using the -n option, the /inet addr/ address, the p flag on the s command, and the q command, essentially has the same effect as grep -m1 "inet addr", which makes calling grep unnecessary. In fact, it's worth noting that the following commands produce identical output:
> ifconfig | grep -m1 "inet addr"
inet addr:192.168.1.1 Bcast:192.168.2.255 Mask:255.255.255.0
> ifconfig | sed -n '/inet addr/{p;q}'
inet addr:192.168.1.1 Bcast:192.168.2.255 Mask:255.255.255.0
Here, I've omitted the s/pattern/replacement/p part of the sed command, and replaced it with a p command (which just prints the whole line), just to show the effect of the other parts in isolation.
Just use the command cut.
ip a | grep -m1 "inet addr" | cut -d':' -f 2 | cut -d' ' -f 1
I also advise you to learn the use of other commands such as : wc,sed,tr,sort,uniq. They will help manipulate the output as you please. Here is a small lesson where we present you all these command : https://www.javatpoint.com/linux-filters
I hope to help you.
Using Bash's regex operator =~:
$ [[ $(ifconfig | grep -m1 "inet addr") =~ [0-9]+\.[0-9]+\.[0-9]+\.[0-9]+ ]] && echo ${BASH_REMATCH[0]}
172.30.1.6
Update: Something even better in the comments.
I use the following command to get the MAC address of the system.
ifconfig | grep enp0s20f6 | awk '{print $5}'
The following command is used to get the hash of the string:
echo -n "string to be hashed"| md5sum | awk '{print $1}'
I need to get the hashed string for the MAC address by combining both of these commands.
I tried the following, but didn't work.
ifconfig | grep enp0s20f6 | awk '{print $5}' | md5sum
md5sum /sys/class/net/eth0/address | awk '{print $1}'
Try this:
$ cat /sys/class/net/eth0/address | md5sum
Replace eth0 by the name of your interface. Hope it helps! :)
md5sum < /sys/class/net/eth0/address
This command also helps to get the md5sum of mac address
I have to store the return of this command into an array
I tried this :
my_array=( $(/sbin/ifconfig | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}' | grep -v '127.0.0.1'))
but it gives me the error below:
/bin: is a directory
You could remove parenthesis as below. You can also use ip command, its newer version and more powerful than ifconfig.
my_array=$(ip addr show | grep -Po 'inet \K[\d.]+' | grep -v 127.0.0.1)
In my GNU bash 4.4.0(1), ifconfig is not giving me inet addr: but just inet like this:
inet 10.0.2.15 netmask 255.255.255.0 broadcast 10.0.2.255
inet 127.0.0.1 netmask 255.0.0.0
In any case the error you receive doesn't make sense to me.
I can get the IP address combining grep & awk like this:
sbin/ifconfig | grep -v "127.0.0.1" |grep 'inet ' |awk -F" " '{print $2}'
(awk -F" " : Field Seperator. Field Seperator in my case is space.)
Also this works for me , due to the fact that 127.0.0.1 goes to the end:
/sbin/ifconfig |grep -m1 'inet '| awk -F" " '{print $2}
(grep -m1 = stop after first match)
PS: If you have plans to append your array , you need to use my_array+=(...)
I am trying to use Bash on CentOS 6.4 to retrieve the network interface name attached to an IP address using AWK. I have a bit of command from a Solaris box, but I'm not sure how to convert it to Linux output.
The command looks like this:
ifconfig -a | awk '
$1 ~ /:/ {split($1,nic,":");
lastif=sprintf("%s:%s",nic[1],nic[2]);}
$2 == "'$1'" { print lastif ; exit; }
'
Its part of a script, so it takes commandline argument like monitor.sh x.x.x.x y.y.y.y and it uses the first x.x.x.x to get the interface name, then makes $1 == $2 so then it can ping y.y.y.y later. I'm guessing that in Solaris the ifconfig -a output is different than CentOS. I can get the interface name if the IP and interface are on the same line, but in linux, they're on two different lines. Any ideas.
I don't have CentOS, but in RHEL, IP address is listed as inet address. I believe they should be same.
The following command should give you the interface name which has a IP address.
export iface=$(ifconfig | grep -B1 "inet addr:x.x.x.x" | awk '$1!="inet" && $1!="--" {print $1}')
echo "$iface" # To get the interface name for x.x.x.x ip
And this one should show the IP including localhost :
ifconfig | grep "inet addr:" | sed -e 's/addr:/addr: /g' | awk '{print $3}'
geting ifname for 127.0.0.1 (or any other IP)
ifconfig | awk '/127.0.0.1/ {print $1}' RS="\n\n"
lo
getting ip:
ifconfig | awk -F"[ :]+" '/inet addr:/ {print $4}'
Post the output of ifconfig, and I can help you fine tune for your OS