diff --git a/package/cla-sysrepo/cla-appliance.service.in b/package/cla-sysrepo/cla-appliance.service.in
index b3ef5b0..b01a7a1 100644
--- a/package/cla-sysrepo/cla-appliance.service.in
+++ b/package/cla-sysrepo/cla-appliance.service.in
@@ -1,9 +1,9 @@
 [Unit]
 Description=CzechLight __MODEL__ driver
-After=syslog.target network.target czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+After=syslog.target network.target cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 Before=rauc-mark-good.service velia-hardware-g1.service velia-hardware-g2.service
 PartOf=netopeer2.service
-Requires=czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+Requires=cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 StartLimitIntervalSec=0
 ConditionKernelCommandLine=|czechlight=__MODEL__
 ConditionKernelCommandLine=|czechlight=__MODEL__-g2
diff --git a/package/czechlight-cfg-fs/czechlight-cfg-fs.mk b/package/czechlight-cfg-fs/czechlight-cfg-fs.mk
index 775b088..5b21b97 100644
--- a/package/czechlight-cfg-fs/czechlight-cfg-fs.mk
+++ b/package/czechlight-cfg-fs/czechlight-cfg-fs.mk
@@ -62,6 +62,17 @@
 			$(TARGET_DIR)/usr/lib/systemd/system/
 		ln -sf ../cfg-restore-systemd-network.service $(TARGET_DIR)/usr/lib/systemd/system/network-pre.target.wants/
 	$(endif)
+
+	$(INSTALL) -D -m 0755 -t $(TARGET_DIR)/usr/libexec/czechlight-cfg-fs \
+		$(BR2_EXTERNAL_CZECHLIGHT_PATH)/package/czechlight-cfg-fs/czechlight-migrate.sh \
+		$(BR2_EXTERNAL_CZECHLIGHT_PATH)/package/czechlight-cfg-fs/czechlight-migration-list.sh
+
+	$(INSTALL) -D -m 0644 -t $(TARGET_DIR)/usr/libexec/czechlight-cfg-fs/migrations \
+		$(BR2_EXTERNAL_CZECHLIGHT_PATH)/package/czechlight-cfg-fs/migrations/*
+
+	$(INSTALL) -D -m 0644 -t $(TARGET_DIR)/usr/lib/systemd/system/ \
+		$(BR2_EXTERNAL_CZECHLIGHT_PATH)/package/czechlight-cfg-fs/czechlight-migrate.service
+	ln -sf ../czechlight-migrate.service $(TARGET_DIR)/usr/lib/systemd/system/multi-user.target.wants/
 endef
 
 # Configure OpenSSH to look for *user* keys in the /cfg
diff --git a/package/czechlight-cfg-fs/czechlight-install-yang.service b/package/czechlight-cfg-fs/czechlight-install-yang.service
index e34aee2..80e89fc 100644
--- a/package/czechlight-cfg-fs/czechlight-install-yang.service
+++ b/package/czechlight-cfg-fs/czechlight-install-yang.service
@@ -2,7 +2,7 @@
 Description=Install CzechLight YANG models
 After=netopeer2-install-yang.service cfg.mount
 Requires=netopeer2-install-yang.service cfg.mount
-Before=netopeer2.service cfg-restore-sysrepo.service
+Before=netopeer2.service cfg-restore-sysrepo.service czechlight-migrate.service
 
 [Service]
 Type=oneshot
diff --git a/package/czechlight-cfg-fs/czechlight-install-yang.sh b/package/czechlight-cfg-fs/czechlight-install-yang.sh
index 6c9f829..77c805d 100755
--- a/package/czechlight-cfg-fs/czechlight-install-yang.sh
+++ b/package/czechlight-cfg-fs/czechlight-install-yang.sh
@@ -58,23 +58,19 @@
         done
     fi
     sysrepoctl --search-dirs ${CLA_YANG} --install ${CLA_YANG}/czechlight-roadm-device@2021-03-05.yang ${FEATURE_ARGS} --permissions 0660
-    sysrepocfg --datastore=startup --format=json --module=czechlight-roadm-device --import="${CLA_YANG}/${INITIAL_DATA}.json"
 fi
 
 if [[ ${YANG_COHERENT} == 1 ]]; then
     sysrepoctl --search-dirs ${CLA_YANG} --install ${CLA_YANG}/czechlight-coherent-add-drop@2021-03-05.yang --permissions 0660
-    sysrepocfg --datastore=startup --format=json --module=czechlight-coherent-add-drop --new-data="${CLA_YANG}/${INITIAL_DATA}.json"
     sysrepoctl --change czechlight-coherent-add-drop --permissions 0660
 fi
 
 if [[ ${YANG_INLINE} == 1 ]]; then
     sysrepoctl --search-dirs ${CLA_YANG} --install ${CLA_YANG}/czechlight-inline-amp@2021-03-05.yang --permissions 0660
-    sysrepocfg --datastore=startup --format=json --module=czechlight-inline-amp --import="${CLA_YANG}/${INITIAL_DATA}.json"
 fi
 
 if [[ ${YANG_CALIBRATION} == 1 ]]; then
     sysrepoctl --search-dirs ${CLA_YANG} --install ${CLA_YANG}/czechlight-calibration-device@2019-06-25.yang --permissions 0660
-    sysrepocfg --datastore=startup --format=json --module=czechlight-calibration-device --import="${CLA_YANG}/${INITIAL_DATA}.json"
 fi
 
 sysrepoctl --search-dirs ${VELIA_YANG} --install ${VELIA_YANG}/ietf-system@2014-08-06.yang --permissions 0660
@@ -93,6 +89,3 @@
 
 sysrepoctl --search-dirs ${VELIA_YANG} --install ${VELIA_YANG}/czechlight-firewall@2021-01-25.yang --permissions 0600
 sysrepoctl --change ietf-access-control-list --enable-feature match-on-eth --enable-feature eth --enable-feature match-on-ipv4 --enable-feature ipv4 --enable-feature match-on-ipv6 --enable-feature ipv6 --enable-feature mixed-eth-ipv4-ipv6
-
-# If not do not copy here from startup -> running, running might be stale.
-sysrepocfg -C startup
diff --git a/package/czechlight-cfg-fs/czechlight-migrate.service b/package/czechlight-cfg-fs/czechlight-migrate.service
new file mode 100644
index 0000000..7e58d4d
--- /dev/null
+++ b/package/czechlight-cfg-fs/czechlight-migrate.service
@@ -0,0 +1,14 @@
+[Unit]
+Description=Migrate CzechLight YANG models startup data
+After=netopeer2-install-yang.service czechlight-install-yang.service cfg-restore-sysrepo.service cfg.mount
+Requires=netopeer2-install-yang.service czechlight-install-yang.service cfg-restore-sysrepo.service cfg.mount
+Before=netopeer2-setup.service netopeer2.service sysrepo-persistent-cfg.service
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/bin/bash /usr/libexec/czechlight-cfg-fs/czechlight-migrate.sh
+Group=sysrepo
+
+[Install]
+WantedBy=multi-user.target
diff --git a/package/czechlight-cfg-fs/czechlight-migrate.sh b/package/czechlight-cfg-fs/czechlight-migrate.sh
new file mode 100755
index 0000000..fd49f60
--- /dev/null
+++ b/package/czechlight-cfg-fs/czechlight-migrate.sh
@@ -0,0 +1,86 @@
+#!/bin/bash
+
+set -ex
+
+SCRIPT_ROOT=$(dirname $(realpath -s $0))
+MIGRATIONS=$SCRIPT_ROOT/czechlight-migration-list.sh
+export MIGRATIONS_DIRECTORY=${SCRIPT_ROOT}/migrations
+CFG_VERSION_FILE="${CFG_VERSION_FILE:-/cfg/sysrepo/version}"
+CFG_STARTUP_FILE="${CFG_STARTUP_FILE:-/cfg/sysrepo/startup.json}"
+PROC_CMDLINE="${PROC_CMDLINE:-/proc/cmdline}"
+
+export CLA_YANG="${CLA_YANG:-/usr/share/cla-sysrepo/yang}"
+export VELIA_YANG="${VELIA_YANG:-/usr/share/velia/yang}"
+
+# load migrations and perform a sanity check (filename's numerical prefix corresponds to the order in the MIGRATIONS array)
+source $MIGRATIONS
+for i in $(seq ${#MIGRATION_FILES[@]}); do
+    FILENAME=${MIGRATION_FILES[$(($i - 1))]}
+
+    if ! [[ "$FILENAME" =~ ^[0-9]{4}_.*.sh$ ]]; then
+        echo "Migration file '$FILENAME' has unexpected name"
+        exit 1
+    fi
+
+    FILE_REV=$(echo "$FILENAME" | grep -Eo "^[0-9]{4}")
+    if [[ $((FILE_REV + 0)) != $i ]]; then
+        echo "Migration filename '$FILENAME' hints revision $(($FILE_REV + 0)) but it is at position $i of the migration array"
+        exit 1
+    fi
+done
+
+for ARG in $(cat "$PROC_CMDLINE"); do
+    case "${ARG}" in
+        czechlight=*)
+            export CZECHLIGHT="${ARG:11}"
+            ;;
+    esac
+done
+
+case "${CZECHLIGHT}" in
+    sdn-roadm-line*)
+        export YANG_ROADM=1
+        ;;
+    sdn-roadm-add-drop*)
+        export YANG_ROADM=1
+        ;;
+    sdn-roadm-hires-add-drop*)
+        export YANG_ROADM=1
+        ;;
+    sdn-roadm-coherent-a-d*)
+        export YANG_COHERENT=1
+        ;;
+    sdn-inline*)
+        export YANG_INLINE=1
+        ;;
+    calibration-box)
+        export YANG_CALIBRATION=1
+        ;;
+esac
+
+
+# we might end up on the system
+# * that was created before the migrations were introduced; such system does not have ${CFG_VERSION_FILE}
+# * that was just created and freshly initialized with firmware; it has ${CFG_VERSION_FILE} but startup.json does not exist
+if [[ -r "$CFG_VERSION_FILE" && -f "$CFG_STARTUP_FILE" ]]; then
+    CURRENT_VERSION="$(cat ${CFG_VERSION_FILE})"
+else
+    CURRENT_VERSION=0
+fi
+
+if [[ ! "$CURRENT_VERSION" =~ ^[0-9]+$ ]]; then
+    echo "Invalid version '$CURRENT_VERSION'"
+    exit 1
+fi
+
+while [[ $CURRENT_VERSION -lt ${#MIGRATION_FILES[@]} ]]; do
+    /bin/bash ${SCRIPT_ROOT}/migrations/${MIGRATION_FILES[$CURRENT_VERSION]}
+    CURRENT_VERSION=$(($CURRENT_VERSION + 1))
+done
+
+# store current version and save startup.json
+sysrepocfg -d startup -f json -X > "$CFG_STARTUP_FILE"
+echo "$CURRENT_VERSION" > "$CFG_VERSION_FILE"
+
+# If not do not copy here from startup -> running, running might be stale.
+sysrepocfg -C startup
diff --git a/package/czechlight-cfg-fs/czechlight-migration-list.sh b/package/czechlight-cfg-fs/czechlight-migration-list.sh
new file mode 100644
index 0000000..9b5a49d
--- /dev/null
+++ b/package/czechlight-cfg-fs/czechlight-migration-list.sh
@@ -0,0 +1,5 @@
+MIGRATION_FILES=(
+    '0001_initial-data.sh'
+)
+
+
diff --git a/package/czechlight-cfg-fs/migrations/0001_initial-data.sh b/package/czechlight-cfg-fs/migrations/0001_initial-data.sh
new file mode 100644
index 0000000..8b81ccb
--- /dev/null
+++ b/package/czechlight-cfg-fs/migrations/0001_initial-data.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+
+# Load initial data
+# -----------------
+# These data are imported into the sysrepo's startup datastore only once. This happens either when the box is restored to
+# its factory settings (the box is new and boots for the first time or someone deletes the startup.json backup in /cfg)
+# or when the box is upgraded from the state before the migrations were introduced (versions released before July 2022).
+#
+# It's OK for user to remove these settings from sysrepo startup DS.
+# However, the data will NEVER get restored by us (unless somebody deletes /cfg/startup.json, see above).
+
+case "${CZECHLIGHT}" in
+    sdn-roadm-line*)
+        sysrepocfg --datastore=startup --format=json --module=czechlight-roadm-device --import="${CLA_YANG}/sdn-roadm-line.json"
+        ;;
+    sdn-roadm-add-drop*)
+        ;& # fallthrough
+    sdn-roadm-hires-add-drop*)
+        sysrepocfg --datastore=startup --format=json --module=czechlight-roadm-device --import="${CLA_YANG}/sdn-roadm-add-drop.json"
+        ;;
+    sdn-roadm-coherent-a-d*)
+        sysrepocfg --datastore=startup --format=json --module=czechlight-coherent-add-drop --import="${CLA_YANG}/sdn-roadm-coherent-a-d.json"
+        ;;
+    sdn-inline*)
+        sysrepocfg --datastore=startup --format=json --module=czechlight-inline-amp --import="${CLA_YANG}/sdn-inline.json"
+        ;;
+    calibration-box)
+        sysrepocfg --datastore=startup --format=json --module=czechlight-calibration-device --import="${CLA_YANG}/calibration-box.json"
+        ;;
+esac
diff --git a/package/czechlight-cfg-fs/nacm-restore.service b/package/czechlight-cfg-fs/nacm-restore.service
index 2cb3dec..4f5e5b9 100644
--- a/package/czechlight-cfg-fs/nacm-restore.service
+++ b/package/czechlight-cfg-fs/nacm-restore.service
@@ -1,7 +1,7 @@
 [Unit]
 Description=Restore NACM rules
-After=netopeer2-install-yang.service czechlight-install-yang.service cfg.mount
-Requires=netopeer2-install-yang.service czechlight-install-yang.service cfg.mount
+After=netopeer2-install-yang.service czechlight-migrate.service cfg.mount
+Requires=netopeer2-install-yang.service czechlight-migrate.service cfg.mount
 Before=netopeer2-setup.service netopeer2.service sysrepo-persistent-cfg.service
 
 [Service]
diff --git a/package/czechlight-cfg-fs/sysrepo-persistent-cfg.service b/package/czechlight-cfg-fs/sysrepo-persistent-cfg.service
index 007bd7b..25991f4 100644
--- a/package/czechlight-cfg-fs/sysrepo-persistent-cfg.service
+++ b/package/czechlight-cfg-fs/sysrepo-persistent-cfg.service
@@ -1,10 +1,11 @@
 [Unit]
 Description=Persisting persistent sysrepo datastores to /cfg
-After=netopeer2.service cfg.mount
-Requires=netopeer2.service cfg.mount
+After=netopeer2.service cfg.mount czechlight-migrate.service
+Requires=netopeer2.service cfg.mount czechlight-migrate.service
 
 [Service]
 Type=simple
 UMask=0077
-ExecStart=/bin/sh -c 'while true; do inotifywait -e CLOSE_WRITE /etc/sysrepo/data/*.startup && mkdir -p /cfg/sysrepo/ && sysrepocfg -d startup -f json -X > /cfg/sysrepo/startup.json; done'
+ExecStartPre=/bin/sh -c 'mkdir -p /cfg/sysrepo/ && sysrepocfg -d startup -f json -X > /cfg/sysrepo/startup.json'
+ExecStart=/bin/sh -c 'while true; do inotifywait -e CLOSE_WRITE /etc/sysrepo/data/*.startup && sysrepocfg -d startup -f json -X > /cfg/sysrepo/startup.json; done'
 Group=sysrepo
diff --git a/package/rousette/rousette.service b/package/rousette/rousette.service
index cb79d27..ba9efbb 100644
--- a/package/rousette/rousette.service
+++ b/package/rousette/rousette.service
@@ -1,8 +1,8 @@
 [Unit]
 Description=RESTCONFish server
-After=syslog.target network.target czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+After=syslog.target network.target cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 PartOf=netopeer2.service
-Requires=czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+Requires=cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 
 [Service]
 Type=simple
diff --git a/package/velia/velia-firewall.service b/package/velia/velia-firewall.service
index 1fdb318..e5dd1d6 100644
--- a/package/velia/velia-firewall.service
+++ b/package/velia/velia-firewall.service
@@ -1,9 +1,9 @@
 [Unit]
 Description=Firewall management via sysrepo
-After=syslog.target network.target czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+After=syslog.target network.target cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 Before=rauc-mark-good.service
 PartOf=netopeer2.service
-Requires=czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+Requires=cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 ConditionKernelCommandLine=czechlight
 
 [Service]
diff --git a/package/velia/velia-hardware-g1.service b/package/velia/velia-hardware-g1.service
index 6e09df3..cb0cd30 100644
--- a/package/velia/velia-hardware-g1.service
+++ b/package/velia/velia-hardware-g1.service
@@ -1,9 +1,9 @@
 [Unit]
 Description=Tracking hardware metrics
-After=syslog.target network.target czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+After=syslog.target network.target cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 Before=rauc-mark-good.service
 PartOf=netopeer2.service
-Requires=czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+Requires=cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 ConditionKernelCommandLine=|czechlight=sdn-inline
 ConditionKernelCommandLine=|czechlight=sdn-roadm-add-drop
 ConditionKernelCommandLine=|czechlight=sdn-roadm-coherent-a-d
diff --git a/package/velia/velia-hardware-g2.service b/package/velia/velia-hardware-g2.service
index 84342b7..8a58eab 100644
--- a/package/velia/velia-hardware-g2.service
+++ b/package/velia/velia-hardware-g2.service
@@ -1,9 +1,9 @@
 [Unit]
 Description=Tracking hardware metrics
-After=syslog.target network.target czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+After=syslog.target network.target cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 Before=rauc-mark-good.service
 PartOf=netopeer2.service
-Requires=czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+Requires=cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 ConditionKernelCommandLine=|czechlight=sdn-inline-g2
 ConditionKernelCommandLine=|czechlight=sdn-roadm-add-drop-g2
 ConditionKernelCommandLine=|czechlight=sdn-roadm-coherent-a-d-g2
diff --git a/package/velia/velia-system.service b/package/velia/velia-system.service
index 6963e91..113be5c 100644
--- a/package/velia/velia-system.service
+++ b/package/velia/velia-system.service
@@ -1,9 +1,9 @@
 [Unit]
 Description=System management via sysrepo
-After=syslog.target network.target czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+After=syslog.target network.target cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 Before=rauc-mark-good.service
 PartOf=netopeer2.service
-Requires=czechlight-install-yang.service cfg-restore-sysrepo.service nacm-restore.service
+Requires=cfg-restore-sysrepo.service czechlight-migrate.service nacm-restore.service
 ConditionKernelCommandLine=czechlight
 
 [Service]