During troubleshooting, it is often required to check a vendor of device in our arp / mac address table. Luckily, there’s a free API that we can query to check it.
Getting mac address list
Depending on the device, there are different commands to get mac-address or arp table. I’ll be using my linux laptop:
[root@centos ~]# arp -a
Let’s now extract mac address. I use awk to print a specific column and > to redirect output to the file
[root@centos ~]# arp -a | awk '{ print $4 }' > ip_list
Making API request
Once we’ve got the desired list of mac addresses, let’s check the vendor by looping through the file and making API call for each mac address.
while read ip; do
curl https://api.macvendors.com/$ip
echo $ip
sleep 1
done <ip_list
We can simply save it to the file and make it executable. Let’s run the script.
[root@centos ~]# sh mac.sh
Philips Lighting BVec-b5-fa-09-30-cb
AzureWave Technology Inc.40-99-22-2c-f2-a3
Cisco Systems, Incd4-8c-b5-0e-2a-a3
Hewlett Packardbc-ea-fa-d5-e4-7f
Cisco Systems, Inc54-78-1a-8e-5d-c1
Cisco Systems, Inc74-88-bb-59-10-d2
Ad-hoc request
We can make our script to take a command line arguments if we want to simply get a vendor of one mac address.
!bin/bash curl https://api.macvendors.com/$1
Let’s test it:
[root@centos ~]# sh check_vendor.sh d4-8c-b5-0e-2a-a3 Cisco Systems, Inc
