JMeter - Generate Random MAC Addresses

[Ajith R]

Hi Team,

I have a JSR223 Sampler with the below script:

import TestApp.MessageRegister;
import TestApp.Message;
import TestApp.MessagePropertyAnnotation;
import TestApp.MessageTypeAnnotation;
import TestApp.RegisteredDeviceStatus;
import com.csa.asn1.MessageType;
import com.csa.asn1.BinaryWriterASN1;
import com.csa.asn1.BitConverter;
import com.csa.asn1.Tag;
import org.apache.commons.codec.binary.Hex;

MessageRegister registerMsg = new MessageRegister();
registerMsg.MacAddress = "60:5B:20:0E:FE:E5";
registerMsg.ManufactureDate = "2024-06-06T18:00:00.0000000Z";
registerMsg.SerialNumber = vars.get("serialNumber");
registerMsg.Model = "Model";
registerMsg.StagedVersion = "1";
registerMsg.RunningVersion = "1";
registerMsg.ManufactureVersion = "1";

byte[] bytes =  registerMsg.ToBytes();

return (Hex.encodeHexString(bytes));

The MAC address need to be randomized. Also, we need to ensure its unique per thread (not iteration).

Please help. Thanks for your support.

Regards,
Ajith

[DT]

You can use the following function to generate a random MAC address:

def macAddress() {
    def rnd = new Random()
    def mac = new StringBuilder()

    (1..6).each {
        int value = rnd.nextInt(256)
        def hexStr = Integer.toHexString(value).padLeft(2, '0')
        mac.append(hexStr)
        if (it < 6) {
            mac.append(':')
        }
    }

    return mac.toString()
}

However "random" doesn't mean "unique" so it would be a good idea to pre-generate as many addresses as you will need somewhere in setUp Thread Group, write them into a file and finally use CSV Data Set Config in the "normal" Thread Group to read these pre-generated values.