diff --git a/Makefile b/Makefile
index 91e51298..de9c088e 100644
--- a/Makefile
+++ b/Makefile
@@ -51,10 +51,9 @@ NETWORK_STORAGE_ADDRESS_PREFIX 	?= 172.18.0
 NETWORK_TENANT_ADDRESS_PREFIX 	?= 172.19.0
 NETWORK_STORAGEMGMT_ADDRESS_PREFIX 	?= 172.20.0
 NETWORK_DESIGNATE_ADDRESS_PREFIX 	?= 172.28.0
+# Additional routes that will be forwarded to nncp and net-attach-def
 INTERNALAPI_HOST_ROUTES ?=
-STORAGE_HOST_ROUTES ?=
 TENANT_HOST_ROUTES ?=
-STORAGEMGMT_HOST_ROUTES ?=
 
 # network isolation
 NETWORK_ISOLATION   ?= true
@@ -2395,6 +2394,8 @@ netattach: export DESIGNATE_PREFIX=${NETWORK_DESIGNATE_ADDRESS_PREFIX}
 netattach: export VLAN_START=${NETWORK_VLAN_START}
 netattach: export VLAN_STEP=${NETWORK_VLAN_STEP}
 netattach: export CTLPLANE_IP_ADDRESS_PREFIX=${NNCP_CTLPLANE_IP_ADDRESS_PREFIX}
+netattach: export NETATT_INTERNALAPI_HOST_ROUTES=${INTERNALAPI_HOST_ROUTES}
+netattach: export NETATT_TENANT_HOST_ROUTES=${TENANT_HOST_ROUTES}
 netattach: namespace ## Creates network-attachment-definitions for the networks the workers are attached via nncp
 	$(eval $(call vars,$@,netattach))
 	bash scripts/gen-netatt.sh
diff --git a/scripts/gen-netatt.sh b/scripts/gen-netatt.sh
index 91416341..9bceaf6d 100644
--- a/scripts/gen-netatt.sh
+++ b/scripts/gen-netatt.sh
@@ -120,8 +120,19 @@ if [ -n "$IPV4_ENABLED" ]; then
     cat >> ${DEPLOY_DIR}/internalapi.yaml <<EOF_CAT
         "range": "${INTERNALAPI_PREFIX}.0/24",
         "range_start": "${INTERNALAPI_PREFIX}.30",
-        "range_end": "${INTERNALAPI_PREFIX}.70"
+        "range_end": "${INTERNALAPI_PREFIX}.70",
 EOF_CAT
+    # In the data-plane adoption scenario A (where different IP subnet ranges
+    # between next-gen and wallaby are used) the net-attach-def needs additional routes.
+    if [ -n "$NETATT_INTERNALAPI_HOST_ROUTES" ]; then
+    cat >> ${DEPLOY_DIR}/internalapi.yaml <<EOF_CAT
+        "routes": [
+          {
+             "dst": "${NETATT_INTERNALAPI_HOST_ROUTES}"
+          }
+        ]
+EOF_CAT
+    fi
 elif [ -n "$IPV6_ENABLED" ]; then
     cat >> ${DEPLOY_DIR}/internalapi.yaml <<EOF_CAT
         "range": "fd00:bbbb::/64",
@@ -188,8 +199,19 @@ if [ -n "$IPV4_ENABLED" ]; then
     cat >> ${DEPLOY_DIR}/tenant.yaml <<EOF_CAT
         "range": "${TENANT_PREFIX}.0/24",
         "range_start": "${TENANT_PREFIX}.30",
-        "range_end": "${TENANT_PREFIX}.70"
+        "range_end": "${TENANT_PREFIX}.70",
 EOF_CAT
+    # In the data-plane adoption scenario A (where different IP subnet ranges
+    # between next-gen and wallaby are used) the net-attach-def needs additional routes.
+    if [ -n "$NETATT_TENANT_HOST_ROUTES" ]; then
+    cat >> ${DEPLOY_DIR}/tenant.yaml <<EOF_CAT
+        "routes": [
+          {
+             "dst": "${NETATT_TENANT_HOST_ROUTES}"
+          }
+        ]
+EOF_CAT
+    fi
 elif [ -n "$IPV6_ENABLED" ]; then
     cat >> ${DEPLOY_DIR}/tenant.yaml <<EOF_CAT
         "range": "fd00:dddd::/64",