diff -Nru partman-iscsi-40ubuntu3/debian/changelog partman-iscsi-40ubuntu4.18.10.1/debian/changelog
--- partman-iscsi-40ubuntu3/debian/changelog	2016-03-02 14:55:00.000000000 -0300
+++ partman-iscsi-40ubuntu4.18.10.1/debian/changelog	2019-03-07 15:53:09.000000000 -0300
@@ -1,3 +1,13 @@
+partman-iscsi (40ubuntu4.18.10.1) cosmic; urgency=medium
+
+  * Add support for different network interfaces and iscsi_auto for iBFT. (LP: #1817321)
+    - debian/partman-iscsi.template: add partman-iscsi/iscsi_auto option.
+    - finish.d/iscsi_settings: handle non-default interface for iSCSI.
+    - finish.d/iscsi_settings: check option to include ISCSI_AUTO=true
+      instead of ISCSI_* variables in /etc/iscsi/iscsi.initramfs.
+
+ -- Mauricio Faria de Oliveira <mfo@canonical.com>  Thu, 07 Mar 2019 15:53:09 -0300
+
 partman-iscsi (40ubuntu3) xenial; urgency=medium
 
   * choose_partition/iscsi/do_option: make use of iscsi_start rather than just
diff -Nru partman-iscsi-40ubuntu3/debian/partman-iscsi.templates partman-iscsi-40ubuntu4.18.10.1/debian/partman-iscsi.templates
--- partman-iscsi-40ubuntu3/debian/partman-iscsi.templates	2016-03-01 17:42:15.000000000 -0300
+++ partman-iscsi-40ubuntu4.18.10.1/debian/partman-iscsi.templates	2019-03-07 15:53:09.000000000 -0300
@@ -104,3 +104,10 @@
  Logging into the iSCSI target ${TARGET} on ${PORTAL} failed.
  .
  Check /var/log/syslog or see virtual console 4 for the details.
+
+Template: partman-iscsi/iscsi_auto
+Type: boolean
+Default: false
+Description: for internal use; can be preseeded
+ Use ISCSI_AUTO=true instead of the ISCSI_* variables
+ in the /etc/iscsi/iscsi.initramfs configuration file.
diff -Nru partman-iscsi-40ubuntu3/finish.d/iscsi_settings partman-iscsi-40ubuntu4.18.10.1/finish.d/iscsi_settings
--- partman-iscsi-40ubuntu3/finish.d/iscsi_settings	2015-12-02 14:26:47.000000000 -0200
+++ partman-iscsi-40ubuntu4.18.10.1/finish.d/iscsi_settings	2019-03-07 15:53:09.000000000 -0300
@@ -15,6 +15,17 @@
 	fi
 }
 
+get_address_interface () {
+	local address="$1"
+	[ -n "$address" ] || return 1
+
+	local dev="$(ip route get "$address" 2>/dev/null | \
+			grep -w dev | tr -s ' ' | cut -d' ' -f3)"
+	[ -d "/sys/class/net/$dev" ] || return 1
+
+	address_interface="$dev"
+}
+
 have_iscsi=
 portal=
 target=
@@ -64,28 +75,48 @@
 	ip="${portal%%:*}"
 	port="${portal#*:}"
 	mkdir -p /target/etc/iscsi
-	get_default_interface
-	if [ -f "/sys/class/net/$default_interface/address" ]; then
+
+	# The network interface for iSCSI may not be the default interface.
+	# Try to detect it based on iSCSI portal IP address, and prefer it.
+	if get_address_interface "$ip"; then
+		iscsi_interface="$address_interface"
+	elif get_default_interface; then
+		iscsi_interface="$default_interface"
+	else
+		iscsi_interface=""
+	fi
+
+	db_get partman-iscsi/iscsi_auto || RET="false"
+	if [ "$RET" = true ]; then
 		cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
-HWADDR="$(cat "/sys/class/net/$default_interface/address")"
+ISCSI_AUTO=true
 EOF
-	fi
-	cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
+	else
+		if [ -n "$iscsi_interface" ] &&
+		   [ -f "/sys/class/net/$iscsi_interface/address" ]; then
+			cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
+HWADDR="$(cat "/sys/class/net/$iscsi_interface/address")"
+EOF
+		fi
+		cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
 ISCSI_TARGET_NAME="$target"
 ISCSI_TARGET_IP="$ip"
 ISCSI_TARGET_PORT="$port"
 ISCSI_TARGET_GROUP="$group"
 EOF
-	if [ "$username" ] && [ "$username" != "(null)" ]; then
-		cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
+		if [ "$username" ] &&
+		   [ "$username" != "(null)" ]; then
+			cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
 ISCSI_USERNAME="$username"
 ISCSI_PASSWORD="$password"
 EOF
-		if [ "$username_in" ] && [ "$username_in" != "(null)" ]; then
-			cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
+			if [ "$username_in" ] &&
+			   [ "$username_in" != "(null)" ]; then
+				cat >>/target/etc/iscsi/iscsi.initramfs <<EOF
 ISCSI_IN_USERNAME="$username_in"
 ISCSI_IN_PASSWORD="$password_in"
 EOF
+			fi
 		fi
 	fi
 	chmod 600 /target/etc/iscsi/iscsi.initramfs
@@ -93,11 +124,8 @@
 	# This isn't ideal, but ifupdown doesn't expose any interface that
 	# might allow the initramfs to dynamically tell it to avoid a
 	# particular interface on this boot.
-	if db_get netcfg/choose_interface; then
-		# Work around netcfg/choose_interface not always being set:
-		#   https://bugs.launchpad.net/ubuntu/+source/netcfg/+bug/430820
-		[ "$RET" ] || RET=eth0
-		sed -i "s/\(iface ${RET%%:*} inet\) dhcp/\1 manual/" \
+	if [ -n "$iscsi_interface" ]; then
+		sed -i "s/\(iface $iscsi_interface inet\) dhcp/\1 manual/" \
 			/etc/network/interfaces || true
 	fi
 else