Using grep for bash outputs

Question

I want find servers that not using "net" command. So, I'll run a script from remote. The script is like that:

for ip in $(cat ip_list_file)
do
    netCom=$(ssh -o ConnectTimeout=2 -o StrictHostKeyChecking=no -o PasswordAuthentication=no $ip "net ads info | grep -i command | wc -l")
    if [ $netCom -eq 1 ]
    then 
        echo -e $ip >> not_installed
    else
        echo -e $ip >> installed
    fi
done

But I have a problem at "net ads info | grep -i command | wc -l" command, because I was thinking I can use "bash: net: command not found..." sentence but I can't. I don't want reverse my script like find installed. My question is this: How can I use grep command for the outputs like "bash: net: command not found..."?

Answer 1

The error message is printed to stderr, so you need to redirect it to stdout instead, in order for grep to find it.

for ip in $(cat ip_list_file)
do
    netCom=$(ssh -o ConnectTimeout=2 -o StrictHostKeyChecking=no -o PasswordAuthentication=no $ip "net ads info 2>&1 | grep -i command | wc -l")
    if [ $netCom -eq 1 ]
    then 
        echo -e $ip >> not_installed
    else
        echo -e $ip >> installed
    fi
done