Bash scripting help...

[Oliver Schulze L.]

You can try this:
MAC=$(arping -f -I eth0 $ipnumber | grep reply | tr -s ' ' | tr ']' '[' 
| cut -d '[' -f 2)
echo "MAC: $MAC"

You can debug like this:
echo "Unicast reply from 10.0.0.3 [00:0C:29:C8:DE:E2]  1.040ms" | grep 
reply | tr -s ' ' | tr ']' '[' | cut -d '[' -f 2

HTH
Oliver

-- 
Oliver Schulze L.
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