miio

check_dns() {
    nslookup $1 2>1 | grep Name | wc -l
}

generate_domain() {
    characters="abcdefghijklmnopqrstuwxyz0123456789"
    for i in {0..34} ; do
        for j in {0..34} ; do
            local res=$(check_dns ${characters:$i:1}${characters:$j:1}.api.io.mi.com)
            if [ $res -eq 1 ]
            then
                echo ${characters:$i:1}${characters:$j:1}.api.io.mi.com
            fi
        done
    done
}

de.api.io.mi.com
in.api.io.mi.com
i2.api.io.mi.com
p1.api.io.mi.com
ru.api.io.mi.com
sg.api.io.mi.com
st.api.io.mi.com
tw.api.io.mi.com
us.api.io.mi.com