diff --git a/cmd/scan.go b/cmd/scan.go
index d03e734..5f4ec53 100644
--- a/cmd/scan.go
+++ b/cmd/scan.go
@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"fmt"
+	"net"
 	"os"
 	"path"
 
@@ -16,6 +17,7 @@ var (
 	begin   uint8
 	end     uint8
 	subnets []string
+	subnetMasks []net.IP
 	disableProbing bool
 )
 
@@ -28,8 +30,16 @@ var scanCmd = &cobra.Command{
 		if len(hosts) > 0 {
 			hostsToScan = hosts
 		} else {
-			for _, subnet := range subnets {
-				hostsToScan = append(hostsToScan, magellan.GenerateHosts(subnet, begin, end)...)
+			for i, subnet := range subnets {
+				if len(subnet) <= 0 {
+					return
+				}
+
+				if len(subnetMasks) < i + 1 {
+					subnetMasks = append(subnetMasks, net.IP{255, 255, 255, 0})
+				}
+				
+				hostsToScan = append(hostsToScan, magellan.GenerateHosts(subnet, &subnetMasks[i])...)
 			}
 		}
 
@@ -63,9 +73,10 @@ var scanCmd = &cobra.Command{
 func init() {
 	scanCmd.Flags().StringSliceVar(&hosts, "host", []string{}, "set additional hosts to scan")
 	scanCmd.Flags().IntSliceVar(&ports, "port", []int{}, "set the ports to scan")
-	scanCmd.Flags().Uint8Var(&begin, "begin", 0, "set the starting point for range of IP addresses")
-	scanCmd.Flags().Uint8Var(&end, "end", 255, "set the ending point for range of IP addresses")
+	// scanCmd.Flags().Uint8Var(&begin, "begin", 0, "set the starting point for range of IP addresses")
+	// scanCmd.Flags().Uint8Var(&end, "end", 255, "set the ending point for range of IP addresses")
 	scanCmd.Flags().StringSliceVar(&subnets, "subnet", []string{}, "set additional subnets")
+	scanCmd.Flags().IPSliceVar(&subnetMasks, "subnet-mask", []net.IP{}, "set the subnet masks to use for network")
 	scanCmd.Flags().BoolVar(&disableProbing, "disable-probing", false, "disable probing scanned results for BMC nodes")
 
 	rootCmd.AddCommand(scanCmd)
diff --git a/internal/scan.go b/internal/scan.go
index beee775..d30a51a 100644
--- a/internal/scan.go
+++ b/internal/scan.go
@@ -2,6 +2,7 @@ package magellan
 
 import (
 	"fmt"
+	"math"
 	"net"
 	"net/http"
 	"sync"
@@ -50,12 +51,47 @@ func rawConnect(host string, ports []int, timeout int, keepOpenOnly bool) []Scan
 	return results
 }
 
-func GenerateHosts(subnet string, begin uint8, end uint8) []string {
+
+func GenerateHosts(subnet string, subnetMask *net.IP) []string {
+	if subnet == "" || subnetMask == nil {
+		return nil
+	}
+
+	// convert subnets from string to net.IP
+	subnetIp := net.ParseIP(subnet)
+	if subnetIp == nil {
+		// try parse CIDR instead
+		ip, network, err := net.ParseCIDR(subnet)
+		if err != nil {
+			return nil
+		}
+		subnetIp = ip
+		if network != nil {
+			t := net.IP(network.Mask)
+			subnetMask = &t 
+		}
+	}
+
+	mask := net.IPMask(subnetMask.To4())
+
+	// if no subnet mask, use a default 24-bit mask (for now)
+	return generateHosts(&subnetIp, &mask)
+}
+
+func generateHosts(ip *net.IP, mask *net.IPMask) []string {
+	// get all IP addresses in network
+	ones, _ := mask.Size()
 	hosts := []string{}
-	ip := net.ParseIP(subnet).To4()
-	for i := begin; i < end; i++ {
-		ip[3] = byte(i)
-		hosts = append(hosts, fmt.Sprintf("%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]))
+	end := int(math.Pow(2, float64((32-ones))))-1
+	for i := 0; i < end; i++ {
+		// ip[3] = byte(i)
+		ip = util.GetNextIP(ip, 1)
+		if ip == nil {
+			continue
+		}
+		// host := fmt.Sprintf("%v.%v.%v.%v", (*ip)[0], (*ip)[1], (*ip)[2], (*ip)[3])
+		// fmt.Printf("host: %v\n", ip.String())
+		hosts = append(hosts, ip.String())
 	}
 	return hosts
 }
diff --git a/internal/util/util.go b/internal/util/util.go
index 990bda9..15b3f69 100644
--- a/internal/util/util.go
+++ b/internal/util/util.go
@@ -5,6 +5,7 @@ import (
 	"crypto/tls"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"os"
 	"time"
@@ -17,6 +18,22 @@ func PathExists(path string) (bool, error) {
 	return false, err
 }
 
+func GetNextIP(ip *net.IP, inc uint) *net.IP {
+	if ip == nil {
+		return &net.IP{}
+	}
+	i := ip.To4()
+	v := uint(i[0])<<24 + uint(i[1])<<16 + uint(i[2])<<8 + uint(i[3])
+	v += inc
+	v3 := byte(v & 0xFF)
+	v2 := byte((v >> 8) & 0xFF)
+	v1 := byte((v >> 16) & 0xFF)
+	v0 := byte((v >> 24) & 0xFF)
+	// return &net.IP{[]byte{v0, v1, v2, v3}}
+	r := net.IPv4(v0, v1, v2, v3)
+	return &r
+}
+
 func MakeRequest(url string, httpMethod string, body []byte, headers map[string]string) (*http.Response, []byte, error) {
 	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
 	req, err := http.NewRequest(httpMethod, url, bytes.NewBuffer(body))