3 files changed, 56 insertions, 1 deletions
diff --git a/configuration/debian/tedge_agent/prerm b/configuration/debian/tedge_agent/prerm
new file mode 100644
index 00000000..ef5833cd
--- /dev/null
+++ b/configuration/debian/tedge_agent/prerm
@@ -0,0 +1,12 @@
+#!/bin/sh
+
+set -e
+
+print_hint() {
+    echo "$1 is running. Stop $1 before installation, to stop it use: systemctl stop $1"
+}
+
+if systemctl is-active --quiet tedge-agent; then
+    print_hint "tedge-agent"
+    exit 1
+fi
diff --git a/configuration/debian/tedge_mapper/prerm b/configuration/debian/tedge_mapper/prerm
new file mode 100644
index 00000000..4b7a037b
--- /dev/null
+++ b/configuration/debian/tedge_mapper/prerm
@@ -0,0 +1,30 @@
+#!/bin/sh
+
+set -e
+
+print_hint() {
+    echo "$1 is running. Stop $1 before installation, use: systemctl stop $1"
+    echo "If you want to start $1 after installation, use: systemctl restart $1"
+    echo "Make sure that other mappers are not running: systemctl is-active [mapper_name]"
+    echo "Known mappers are: tedge-mapper-c8y, tedge-mapper-collectd, tedge-mapper-sm-c8y, tedge-mapper-az".
+}
+
+if systemctl is-active --quiet tedge-mapper-c8y; then
+    print_hint "tedge-mapper-c8y"
+    exit 1
+fi
+
+if systemctl is-active --quiet tedge-mapper-sm-c8y; then
+    print_hint "tedge-mapper-sm-c8y"
+    exit 1
+fi
+
+if systemctl is-active --quiet tedge-mapper-collectd; then
+    print_hint "tedge-mapper-collectd"
+    exit 1
+fi
+
+if systemctl is-active --quiet tedge-mapper-az; then
+    print_hint "tedge-mapper-az"
+    exit 1
+fi
diff --git a/docs/src/howto-guides/002_installation.md b/docs/src/howto-guides/002_installation.md
index 1b087c5f..7a3d414c 100644
--- a/docs/src/howto-guides/002_installation.md
+++ b/docs/src/howto-guides/002_installation.md
@@ -3,9 +3,11 @@
 ## Installation with get-thin-edge_io.sh script
 
 There are two possibilities to install thin-edge.io, the easiest way is to use the installation script with this command:
-```
+
+```shell
 curl -fsSL https://raw.githubusercontent.com/thin-edge/thin-edge.io/main/get-thin-edge_io.sh | sudo sh -s
 ```
+
 You can execute that command on your device and it will do all required steps for an initial setup.
 
 If you prefer to have a little more control over the installation or the script did not work for you, please go on with the following steps.
@@ -33,6 +35,17 @@ sudo apt install mosquitto
 
 When all dependencies are in place you can proceed with installation of `thin-edge.io cli` and `thin-edge.io mapper` service.
 
+### Upgrading `thin-edge.io`
+
+If you already have `thin-edge.io` on your device to upgrade `thin-edge.io` follow the steps below, there is no need to remove old version.
+
+> Note: To successfully upgrade `thin-edge.io` all thin-edge.io components should be stopped, eg: `tedge-mapper` and `tedge-agent`:
+>
+> ```shell
+> systemctl stop tedge-mapper-c8y
+> systemctl stop tedge-agent
+> ```
+
 ### Package download
 
 thin-edge.io package is in thin-edge.io repository on GitHub: [thin-edge.io](https://github.com/thin-edge/thin-edge.io/releases).