diff --git a/cmd/start.go b/cmd/start.go
index fafffe7..c8c3639 100644
--- a/cmd/start.go
+++ b/cmd/start.go
@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"github.com/c-robinson/iplib"
 	log "github.com/sirupsen/logrus"
-	"io/ioutil"
 	"net"
 	"os"
 	"regexp"
@@ -13,21 +12,18 @@ import (
 	"strings"
 )
 
-// FIXME : Do not work?!
 func setJailConfigUpdated(jail *Jail) error {
 	if len(jail.ConfigPath) == 0 {
 		return errors.New(fmt.Sprintf("No config path for jail %s", jail.Name))
 	}
 
-	for i, j := range gJails {
-		if jail.Name == j.Name {
-			fmt.Printf("Tag %s as configUpdated\n", jail.Name)
-			gJails[i].ConfigUpdated = true
-			return nil
-		}
+	j, err := getJailFromArray(jail.Name, gJails)
+	if err != nil {
+		return err
 	}
-
-	return errors.New("Jail not found")
+	j.ConfigUpdated = true
+	
+	return nil
 }
 
 func mountProcFs(jail *Jail) error {
@@ -194,12 +190,18 @@ func mountAllJailFsFromHost(jail *Jail) error {
 func prepareJailedZfsDatasets(jail *Jail) error {
 	if jail.Config.Jail_zfs > 0 {
 		// For jail to mount filesystem, enforce_statfs should be 1 or lower (2 is the default)
-		// TODO : Write these changes in jail config file
-		jail.Config.Allow_mount = 1
-		jail.Config.Allow_mount_zfs = 1
+		if jail.Config.Allow_mount != 1 {
+			jail.Config.Allow_mount = 1
+			setJailConfigUpdated(jail)
+		}
+		if jail.Config.Allow_mount_zfs != 1 {
+			jail.Config.Allow_mount_zfs = 1
+			setJailConfigUpdated(jail)
+		}
 		// TODO : Overload Json Unmarshalling to fix bad typed values, keeping iocage compatibility
 		if jail.Config.Enforce_statfs > "1" {
 			jail.Config.Enforce_statfs = "1"
+			setJailConfigUpdated(jail)
 		}
 		for _, d := range strings.Split(jail.Config.Jail_zfs_dataset, " ") {
 			// Check if dataset exist, create if necessary
@@ -450,14 +452,7 @@ func genNatIpv4(jail *Jail) ([]string, error) {
 
 func buildDevfsRuleSet(jail *Jail) (error, int) {
 	rulesets := []int{}
-	// TODO : Could be replaced by "add include $devfsrules_unhide_login" (see /etc/devfs.rules)
-	/*default_devs := [47]string {"hide", "null", "zero", "crypto", "random", "urandom", "ptyp*",
-		"ptyq*", "ptyr*", "ptys*", "ptyP*", "ptyQ*", "ptyR*", "ptyS*", "ptyl*",
-		"ptym*", "ptyn*", "ptyo*", "ptyL*", "ptyM*", "ptyN*", "pty0*", "ttyp*",
-		"ttyq*", "ttyr*", "ttys*", "ttyP*", "ttyQ*", "ttyR*", "ttyS*", "ttyl*",
-		"ttym*", "ttyn*", "ttyo*", "ttyL*", "ttyM*", "ttyN*", "tty0*", "ptmx",
-		"pts", "pts/*", "fd", "fd/*", "stdin", "stdout", "stderr", "zfs"}
-	*/
+	
 	// Get known rulesets
 	out, err := executeCommand("devfs rule showsets")
 	if err != nil {
@@ -480,22 +475,25 @@ func buildDevfsRuleSet(jail *Jail) (error, int) {
 		}
 	}
 	
+	log.Debug("buildDevfsRuleSet: Build ruleset %d\n", ruleset)
+	
 	// Get default devfs_ruleset for the datastore
-	ds, err := getDatastoreFromArray(jail.Datastore, gDatastores)
+	// UPDATE: We don't need this as every jail have a default Devfs_ruleset value
+	/*ds, err := getDatastoreFromArray(jail.Datastore, gDatastores)
 	if err != nil {
 		return errors.New(fmt.Sprintf("Error getting datastore %s for jail %s", jail.Datastore, jail.Name)), 0
 	}
 	defaultrs, err := strconv.ParseInt(ds.DefaultJailConfig.Devfs_ruleset, 10, 64)
 	if err != nil {
 		return errors.New(fmt.Sprintf("Error parsing default devfs_ruleset for datastore %s", jail.Datastore)), 0
-	}
+	}*/
 	
-	// Clone configured devfs_rulesetto a dynamic ruleset
+	// Clone configured devfs_ruleset to a dynamic ruleset
 	if false == isStringInArray(srs, jail.Config.Devfs_ruleset) {
 		return errors.New(fmt.Sprintf("Unknown ruleset: %s", jail.Config.Devfs_ruleset)), 0
 	}
 	rs, _ := strconv.Atoi(jail.Config.Devfs_ruleset)
-	err := copyDevfsRuleset(ruleset, rs)
+	err = copyDevfsRuleset(ruleset, rs)
 	if err != nil {
 		return err, 0
 	}
@@ -523,6 +521,204 @@ func buildDevfsRuleSet(jail *Jail) (error, int) {
 	return nil, ruleset
 }
 
+/*****************************************************************************
+ * Build the file containing jail start parameters, in 
+ *   /var/run/jail.${jail_internal_name}.conf
+ ****************************************************************************/
+func buildJailParameters(jail *Jail, dynruleset int) error {
+	parameterFilePath := fmt.Sprintf("/var/run/jail.%s.conf", jail.InternalName)
+	
+	pfile, err := os.Create(parameterFilePath)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Unable to create file /var/run/jail.%d.conf", jail.InternalName))
+	}
+	defer pfile.Close()
+	
+	if _, err = pfile.WriteString(fmt.Sprintf("%s {\n", jail.InternalName)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	
+	if jail.Config.Vnet > 0 { 
+		if _, err = pfile.WriteString("    vnet;\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	// FreeBSD 9.3 and under do not support these 2 options
+	if gJailHost.version.major > 9 || (gJailHost.version.major == 9 && gJailHost.version.minor > 3) {
+		if _, err = pfile.WriteString("    mount.fdescfs = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+		if jail.Config.Allow_mount_tmpfs > 0 {
+			if _, err = pfile.WriteString("    allow.mount.tmpfs = \"1\";\n"); err != nil {
+				return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+			}
+		}
+	}
+	
+	if gJailHost.version.major >= 12 {
+		if jail.Config.Allow_mlock > 0 {
+			if _, err = pfile.WriteString("    allow.mlock = \"1\";\n"); err != nil {
+				return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+			}
+		}
+		if jail.Config.Allow_mount_fusefs > 0 {
+			if _, err = pfile.WriteString("    allow.mount.fusefs = \"1\";\n"); err != nil {
+				return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+			}
+		}
+		if jail.Config.Allow_vmm > 0 {
+			if _, err = pfile.WriteString("    allow.vmm = \"1\";\n"); err != nil {
+				return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+			}
+		}
+	}
+	
+	if jail.Config.Allow_set_hostname > 0 {
+		if _, err = pfile.WriteString("    allow.set_hostname = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Mount_devfs > 0 {
+		if _, err = pfile.WriteString("    mount.devfs = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_raw_sockets > 0 {
+		if _, err = pfile.WriteString("    allow.raw_sockets = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_sysvipc > 0 {
+		if _, err = pfile.WriteString("    allow.sysvipc = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_quotas > 0 {
+		if _, err = pfile.WriteString("    allow.quotas = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_socket_af > 0 {
+		if _, err = pfile.WriteString("    allow.socket_af = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_chflags > 0 {
+		if _, err = pfile.WriteString("    allow.chflags = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_mount > 0 {
+		if _, err = pfile.WriteString("    allow.mount = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_mount_devfs > 0 {
+		if _, err = pfile.WriteString("    allow.mount.devfs = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_mount_nullfs > 0 {
+		if _, err = pfile.WriteString("    allow.mount.nullfs = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_mount_procfs > 0 {
+		if _, err = pfile.WriteString("    allow.mount.procfs = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if jail.Config.Allow_mount_zfs > 0 {
+		if _, err = pfile.WriteString("    allow.mount.zfs = \"1\";\n"); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if gJailHost.version.major > 10 || (gJailHost.version.major == 10 && gJailHost.version.minor > 3) {
+		if _, err = pfile.WriteString(fmt.Sprintf("    sysvmsg = \"%s\";\n", jail.Config.Sysvmsg)); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+		if _, err = pfile.WriteString(fmt.Sprintf("    sysvsem = \"%s\";\n", jail.Config.Sysvsem)); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+		if _, err = pfile.WriteString(fmt.Sprintf("    sysvshm = \"%s\";\n", jail.Config.Sysvshm)); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if gJailHost.version.major >= 12 {
+		if _, err = pfile.WriteString(fmt.Sprintf("    exec.created = \"%s\";\n", jail.Config.Exec_created)); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    host.domainname = \"%s\";\n", jail.Config.Host_domainname)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    host.hostname = \"%s\";\n", jail.Config.Host_hostname)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    path = \"%s\";\n", jail.RootPath)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    securelevel = \"%s\";\n", jail.Config.Securelevel)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	
+	// FIXME : Handle the same name jail on different datastores
+	if _, err = pfile.WriteString(fmt.Sprintf("    host.hostuuid = \"%s\";\n", jail.Config.Host_hostuuid)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	
+	if _, err = pfile.WriteString(fmt.Sprintf("    devfs_ruleset = \"%d\";\n", dynruleset)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    enforce_statfs = \"%s\";\n", jail.Config.Enforce_statfs)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    children.max = \"%s\";\n", jail.Config.Children_max)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    exec.clean = \"%d\";\n", jail.Config.Exec_clean)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    exec.timeout = \"%s\";\n", jail.Config.Exec_timeout)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString(fmt.Sprintf("    stop.timeout = \"%s\";\n", jail.Config.Stop_timeout)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	splits := strings.Split(jail.RootPath, "/")
+	fstabPath := strings.Join(append(splits[:len(splits)-1], 
+									 strings.Replace(splits[len(splits)-1], "root", "fstab", 1)), "/")
+	if _, err = pfile.WriteString(fmt.Sprintf("    mount.fstab = \"%s\";\n", fstabPath)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if _, err = pfile.WriteString("    allow.dying;\n"); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	// get current datastore to get mountpoint
+	ds, err := getDatastoreFromArray(jail.Datastore, gDatastores)
+	if err != nil {
+		return errors.New(fmt.Sprintf("Unable to get datastore %s for jail %s", jail.Datastore, jail.Name))
+	}
+	consolelog := fmt.Sprintf("%s/log/%s-console.log", ds.Mountpoint, jail.InternalName)
+	if _, err = pfile.WriteString(fmt.Sprintf("    exec.consolelog = \"%s\";\n", consolelog)); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	if jail.Config.Ip_hostname > 0 {
+		if _, err = pfile.WriteString(fmt.Sprintf("    ip_hostname = \"%s\";\n", jail.Config.Ip_hostname)); err != nil {
+			return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+		}
+	}
+	if _, err = pfile.WriteString("    persist;\n"); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	
+	if _, err = pfile.WriteString("}\n"); err != nil {
+		return errors.New(fmt.Sprintf("Unable to write to file /var/run/jail.%d.conf: %v", jail.InternalName, err))
+	}
+	return nil
+}
+
+
 /*
 	Start jail:
 		Check jail fstab?
@@ -574,13 +770,7 @@ func StartJail(args []string) {
 		}
 
 		if len(cj.Config.Hostid) > 0 && cj.Config.Hostid_strict_check > 0 {
-			hostid, err := ioutil.ReadFile("/etc/hostid")
-			if err != nil {
-				fmt.Printf(err.Error())
-				return
-			}
-			hostid = []byte(strings.Replace(string(hostid), "\n", "", -1))
-			if strings.EqualFold(string(hostid), cj.Config.Hostid) == false {
+			if strings.EqualFold(gJailHost.hostid, cj.Config.Hostid) == false {
 				fmt.Printf("hostid is not matching and hostid_strict_check is on. Not starting jail.\n")
 				return
 			}
@@ -721,24 +911,24 @@ func StartJail(args []string) {
 			}
 
 			if cj.Config.Vnet == 0 {
-				log.Debug("Generate NAT IPv4 without VNet")
+				log.Debug("Generate NAT IPv4 without VNet\n")
 				ip4, err := genNatIpv4(cj)
 				if err != nil {
 					fmt.Printf("%s\n", err.Error())
 					return
 				}
 
-				log.Debug("Configuring NAT : Set ip4_addr to %s", ip4[0])
+				log.Debug("Configuring NAT : Set ip4_addr to %s\n", ip4[0])
 				// This IP should not be saved into json
 				cj.Config.Ip4_addr = fmt.Sprintf("%s|%s", cj.Config.Nat_interface, ip4[0])
 			} else {
-				log.Debug("Generate NAT IPv4 with VNet")
+				log.Debug("Generate NAT IPv4 with VNet\n")
 				ip4, err := genNatIpv4(cj)
 				if err != nil {
 					fmt.Printf("%s\n", err.Error())
 					return
 				}
-				log.Debug("Configuring NAT : Set ip4_addr to %s, defaultrouter to %s", ip4[1], ip4[0])
+				log.Debug("Configuring NAT : Set ip4_addr to %s, defaultrouter to %s\n", ip4[1], ip4[0])
 				// This IP should not be saved into json
 				cj.Config.Ip4_addr = fmt.Sprintf("vnet0|%s", ip4[1])
 				cj.Config.Defaultrouter = ip4[0]
@@ -757,14 +947,21 @@ func StartJail(args []string) {
 			net = append(net,  strings.Split(cj.Config.Vnet_interfaces, " ")...)
 		}
 		
-		err, rs := buildDevfsRuleSet(cj)
+		err, dynrs := buildDevfsRuleSet(cj)
 		if err != nil {
 			fmt.Printf("%s\n", err.Error())
 			return
 		}
-		// CONTINUE HERE, around https://github.com/iocage/iocage/blob/master/iocage_lib/ioc_start.py:516
-		fmt.Printf("Built ruleset: %d\n", rs)
 		
+		// CONTINUE HERE, around https://github.com/iocage/iocage/blob/master/iocage_lib/ioc_start.py:516		
+		err = buildJailParameters(cj, dynrs)
+		if err != nil {
+			fmt.Printf("%s\n", err.Error())
+			return
+		}
+		
+		// Synchronize jail config to disk
+		WriteConfigToDisk(false)
 
 		/*
 			out, err := executeCommand(fmt.Sprintf("rctl jail:%s", cj.InternalName))