diff --git a/tools/arkmanager b/tools/arkmanager
index 4151663..f126580 100755
--- a/tools/arkmanager
+++ b/tools/arkmanager
@@ -835,6 +835,22 @@ doUpdate() {
     fi
   done
 
+  echo "$$" >"${arkserverroot}/.ark-update.lock.$$"
+  while true; do
+    if ! ln "${arkserverroot}/.ark-update.lock.$$" "${arkserverroot}/.ark-update.lock"; then
+      local lockpid="$(<"${arkserverroot}/.ark-update.lock")"
+      if [ -n "$lockpid" ] && [ "$lockpid" != "$$" ] && kill -0 "$lockpid"; then
+        echo "Update already in progress (PID: $lockpid)"
+	rm -f "${arkserverroot}/.ark-update.lock.$$"
+        return 1
+      fi
+      rm -f "${arkserverroot}/.ark-update.lock"
+    else
+      break
+    fi
+  done
+  rm -f "${arkserverroot}/.ark-update.lock.$$"
+
   if [ -n "$modupdate" ]; then
     if ! doDownloadAllMods; then
       modupdate=
@@ -978,6 +994,8 @@ doUpdate() {
     echo "Your server is already up to date! The most recent version is ${bnumber}."
     echo "`timestamp`: No update needed." >> "$logdir/update.log"
   fi;
+
+  rm -f "${arkserverroot}/.ark-update.lock"
 }
 
 #
diff --git a/tools/install.sh b/tools/install.sh
index f89b155..3c3fbbc 100755
--- a/tools/install.sh
+++ b/tools/install.sh
@@ -218,7 +218,7 @@ else
         cp systemd/arkmanager.service "${INSTALL_ROOT}/etc/systemd/system/arkmanager.service"
         sed -i "s|=/usr/libexec/arkmanager/|=${LIBEXECDIR}/|" "${INSTALL_ROOT}/etc/systemd/system/arkmanager.service"
         cp systemd/arkmanager@.service "${INSTALL_ROOT}/etc/systemd/system/arkmanager@.service"
-        sed -i "s|=/usr/bin/|=${BINDIR}/|" "${INSTALL_ROOT}/etc/systemd/system/arkmanager.service"
+        sed -i "s|=/usr/bin/|=${BINDIR}/|" "${INSTALL_ROOT}/etc/systemd/system/arkmanager@.service"
         if [ -z "${INSTALL_ROOT}" ]; then
           systemctl daemon-reload
           systemctl enable arkmanager.service
@@ -245,7 +245,7 @@ else
         cp systemd/arkmanager.service "${INSTALL_ROOT}/etc/systemd/system/arkmanager.service"
         sed -i "s|=/usr/libexec/arkmanager/|=${LIBEXECDIR}/|" "${INSTALL_ROOT}/etc/systemd/system/arkmanager.service"
         cp systemd/arkmanager@.service "${INSTALL_ROOT}/etc/systemd/system/arkmanager@.service"
-        sed -i "s|=/usr/bin/|=${BINDIR}/|" "${INSTALL_ROOT}/etc/systemd/system/arkmanager.service"
+        sed -i "s|=/usr/bin/|=${BINDIR}/|" "${INSTALL_ROOT}/etc/systemd/system/arkmanager@.service"
         if [ -z "${INSTALL_ROOT}" ]; then
           systemctl daemon-reload
           systemctl enable arkmanager.service