diff --git a/README.org b/README.org
index 5b07a54..846aa1a 100644
--- a/README.org
+++ b/README.org
@@ -745,6 +745,28 @@ export MYSQL_CONTAINER=mailcowdockerized_mysql-mailcow_1
   =compose= à backupper.
 - un serveur =mailcow= est un serveur faisant tourner l'installation =mailcow=.
 
+
+***** Via la commande 0km sur un hôte admin
+
+L'instruction suivante doit être executée sur un hôte ayant la commande
+=0km= d'installée et les accès vers le VPS et un compte administration
+du serveur d'archivage.
+
+#+begin_src sh
+0km vps-install backup myadmin@core-06.0k.io:10023 myvps.fr
+#+end_src
+
+Note: on peut spécifier autant de vps que l'on souhaite en fin de
+ligne de commande.  L'installation des vps se fera en parallèle et
+vers le serveur d'archive spécifié en premier argument.
+
+Note: cette commande peut-être executé plusieurs fois sur le même
+hôte : si tout est déjà installé, cette commande n'aura pour seul
+effet que de relancer une synchronisation vers le backup.
+
+
+***** Via la commande vps sur le vps lui-même
+
 A faire depuis le serveur compose ou mailcow:
 
 #+begin_src sh
diff --git a/bin/0km b/bin/0km
index 5fba286..a87b3a3 100755
--- a/bin/0km
+++ b/bin/0km
@@ -234,6 +234,76 @@ vps_check() {
 }
 
 
+vps_install_backup() {
+    local vps="$1" admin server
+    vps_connection_check "$vps" </dev/null || return 1
+
+    read-0 admin server
+    if ! type=$(ssh:run "root@$vps" -- vps get-type); then
+        err "Could not get type."
+        return 1
+    fi
+
+    if ! out=$(ssh:run "root@$vps" -- vps install backup "$server" 2>&1); then
+        err "Command 'vps install backup $server' failed."
+        return 1
+    fi
+
+    already_present=
+    if e "$out" | grep "^II Entry for service .* is already present" >/dev/null 2>&1; then
+        already_present=1
+        info "Backup entry is already present in 'compose.yml' of '$vps'"
+    fi
+    out="${out%$'\n'}"
+    out="${out#*$'\n'}"
+    key="${out%\'*}"
+    key="${key##*\'}"
+
+    if ! [[ "$key" =~ ^"ssh-rsa "[a-zA-Z0-9/+]+" "[a-zA-Z0-9._-]+"@"[a-zA-Z0-9._-]+$ ]]; then
+        err "Unexpected output from 'vps install backup $server'. Can't find key."
+        echo "$out" | prefix " ${GRAY}|$NORMAL " >&2
+        echo " Extracted key:" >&2
+        echo "$key" | prefix " ${GRAY}|$NORMAL " >&2
+        return 1
+    fi
+
+    if [ "$type" == "compose" ] && [ -z "$already_present" ]; then
+        ssh:run "root@$vps" -- compose --debug up || {
+            err "Command 'compose --debug up' failed."
+            return 1
+        }
+    fi
+
+    dest="$server"
+    dest="${dest%/*}"
+    ssh_options=()
+    if [[ "$dest" == *":"* ]]; then
+        port="${dest##*:}"
+        dest="${dest%%:*}"
+        ssh_options=(-p "$port")
+    else
+        port=""
+        dest="${dest%%:*}"
+    fi
+
+    cmd=(ssh "${ssh_options[@]}" "$admin"@"$dest" ssh-key add "$key")
+    echo "${WHITE}Launching:${NORMAL} ${cmd[@]}"
+
+    "${cmd[@]}" || {
+        err "Failed add key to backup server '$dest'."
+        return 1
+    }
+    echo "${WHITE}Launching backup${NORMAL} from '$vps'"
+
+    ssh:run "root@$vps" -- vps backup || {
+        err "First backup failed to run."
+        return 1
+    }
+
+    echo "Backup is ${GREEN}up and running${NORMAL}."
+}
+
+
 vps_udpate() {
     local vps="$1"
     vps_connection_check "$vps" || return 1
@@ -438,8 +508,39 @@ cmdline.spec::cmd:vps-check:run() {
 }
 
 
-cmdline.spec.gnu vps-update
+cmdline.spec.gnu vps-install
+cmdline.spec::cmd:vps-install:run() {
+    :
+}
+
+cmdline.spec.gnu backup
+cmdline.spec:vps-install:cmd:backup:run() {
+
+    : :posarg: BACKUP_TARGET   'Backup target.
+                                (ie: myadmin@backup.domain.org:10023/256)'
+    : :posarg: [VPS...]        'Target host(s) to check'
 
+
+    if [ "${#VPS[@]}" == 0 ]; then
+        warn "VPS list provided in command line is empty. Nothing will be done."
+        return 0
+    fi
+
+    if ! [[ "$BACKUP_TARGET" == *"@"* ]]; then
+        err "Missing admin account identifier in backup target."
+        echo "  Have you forgottent to specify an account, ie 'myadmin@<MYBACKUP_SERVER>' ?)"
+        return 1
+    fi
+
+    admin=${BACKUP_TARGET%%@*}
+    server=${BACKUP_TARGET#*@}
+    p0 "$admin" "$server" |
+        vps_mux vps_install_backup "${VPS[@]}"
+}
+
+
+
+cmdline.spec.gnu vps-update
 cmdline.spec::cmd:vps-update:run() {
 
     : :posarg: [VPS...]        'Target host to check'