diff --git a/install-release.sh b/install-release.sh
index 9560135..7df8817 100644
--- a/install-release.sh
+++ b/install-release.sh
@@ -26,6 +26,34 @@ JSON_PATH=${JSON_PATH:-/usr/local/etc/xray}
 # Set this variable only if you want this script to check all the systemd unit file:
 # export check_all_service_files='yes'
 
+# Gobal verbals
+# Xray current version
+CURRENT_VERSION=""
+# Xray latest release version
+RELEASE_LATEST=""
+# Xray version will be installed
+INSTALL_VERSION=""
+# --help
+HELP='0'
+# --check
+CHECK='0'
+# --remove
+REMOVE='0'
+# --force
+FORCE='0'
+# --reinstall
+REINSTALL='0'
+# --not-update-service
+N_UP_SERVICE='0'
+# --version ?
+SPECIFIED_VERSION=""
+# --local ?
+LOCAL_FILE=""
+# --proxy ?
+PROXY=""
+# --install-user ?
+INSTALL_USER=""
+
 curl() {
   $(type -P curl) -L -q --retry 5 --retry-delay 10 --retry-max-time 60 "$@"
 }
@@ -148,10 +176,7 @@ identify_the_operating_system_and_architecture() {
 
 ## Demo function for processing parameters
 judgment_parameters() {
-  HELP='0'
-  CHECK='0'
-  REMOVE='0'
-  LOCAL_INSTALL='0'
+  local local_install='0'
   local temp_version='0'
   while [[ "$#" -gt '0' ]]; do
     case "$1" in
@@ -164,7 +189,7 @@ judgment_parameters() {
           exit 1
         fi
         temp_version='1'
-        VERSION="$2"
+        SPECIFIED_VERSION="$2"
         shift
         ;;
       '-c' | '--check')
@@ -177,7 +202,7 @@ judgment_parameters() {
         HELP='1'
         ;;
       '-l' | '--local')
-        LOCAL_INSTALL='1'
+        local_install='1'
         if [[ -z "$2" ]]; then
           echo "error: Please specify the correct local file."
           exit 1
@@ -201,6 +226,12 @@ judgment_parameters() {
         INSTALL_USER="$2"
         shift
         ;;
+      '--reinstall')
+        REINSTALL='1'
+        ;;
+      '--not-update-service')
+        N_UP_SERVICE='1'
+        ;;
       *)
         echo "$0: unknown option -- -"
         exit 1
@@ -212,12 +243,8 @@ judgment_parameters() {
     echo "--help, --check and --remove can't be used together."
     exit 1
   fi
-  if ((temp_version+LOCAL_INSTALL>1)); then
-    echo "--version and --local can't be used together."
-    exit 1
-  fi
-  if ((temp_version+CHECK>1)); then
-    echo "--version and --check can't be used together."
+  if ((temp_version+local_install+REINSTALL>1)); then
+    echo "--version,--reinstall and --local can't be used together."
     exit 1
   fi
 }
@@ -254,31 +281,16 @@ install_software() {
 }
 
 get_current_version() {
+  # Get the CURRENT_VERSION
   if [[ -f '/usr/local/bin/xray' ]]; then
     CURRENT_VERSION="$(/usr/local/bin/xray -version | awk 'NR==1 {print $2}')"
     CURRENT_VERSION="v${CURRENT_VERSION#v}"
+  else
+    CURRENT_VERSION=""
   fi
 }
 
-get_version() {
-  # 0: There is a version can be installed (RELEASE_VERSION).
-  # 1: The current version is the latest.
-  # 2: The specified version is same to the current version.
-  # RELEASE_VERSION, RELEASE_LATEST and CURRENT_VERSION will be used in a later process
-
-  # Get the CURRENT_VERSION
-  get_current_version
-
-  # Check if there is a specified version
-  if [[ -n "$VERSION" ]]; then
-    RELEASE_VERSION="v${VERSION#v}"
-    if [[ "$RELEASE_VERSION" == "$CURRENT_VERSION" ]]; then
-      return 2
-    else
-      return 0
-    fi
-  fi
-
+get_latest_version() {
   # Get Xray latest release version number
   TMP_FILE="$(mktemp)"
   if ! curl -x "${PROXY}" -sS -H "Accept: application/vnd.github.v3+json" -o "$TMP_FILE" 'https://api.github.com/repos/XTLS/Xray-core/releases/latest'; then
@@ -288,31 +300,36 @@ get_version() {
   fi
   RELEASE_LATEST="$(sed 'y/,/\n/' "$TMP_FILE" | grep 'tag_name' | awk -F '"' '{print $4}')"
   if [[ -z "$RELEASE_LATEST" ]]; then
+    "rm" "$TMP_FILE"
     echo "error: Failed to get the latest release version"
     exit 1
   fi
   "rm" "$TMP_FILE"
   RELEASE_LATEST="v${RELEASE_LATEST#v}"
+}
 
-  # Check if the current version is latest
-  RELEASE_VERSION="${RELEASE_LATEST}"
-  if [[ "$RELEASE_VERSION" != "$CURRENT_VERSION" ]]; then
-    RELEASE_VERSIONSION_NUMBER="${RELEASE_VERSION#v}"
-    RELEASE_MAJOR_VERSION_NUMBER="${RELEASE_VERSIONSION_NUMBER%%.*}"
-    RELEASE_MINOR_VERSION_NUMBER="$(echo "$RELEASE_VERSIONSION_NUMBER" | awk -F '.' '{print $2}')"
-    RELEASE_MINIMUM_VERSION_NUMBER="${RELEASE_VERSIONSION_NUMBER##*.}"
+version_gt() {
+  # compare two version
+  # 0: $1 >  $2
+  # 1: $1 <= $2
+
+  if [[ "$1" != "$2" ]]; then
+    local temp_1_version_number="${1#v}"
+    local temp_1_major_version_number="${temp_1_version_number%%.*}"
+    local temp_1_minor_version_number="$(echo "$temp_1_version_number" | awk -F '.' '{print $2}')"
+    local temp_1_minimunm_version_number="${temp_1_version_number##*.}"
     # shellcheck disable=SC2001
-    CURRENT_VERSIONSION_NUMBER="$(echo "${CURRENT_VERSION#v}" | sed 's/-.*//')"
-    CURRENT_MAJOR_VERSION_NUMBER="${CURRENT_VERSIONSION_NUMBER%%.*}"
-    CURRENT_MINOR_VERSION_NUMBER="$(echo "$CURRENT_VERSIONSION_NUMBER" | awk -F '.' '{print $2}')"
-    CURRENT_MINIMUM_VERSION_NUMBER="${CURRENT_VERSIONSION_NUMBER##*.}"
-    if [[ "$RELEASE_MAJOR_VERSION_NUMBER" -gt "$CURRENT_MAJOR_VERSION_NUMBER" ]]; then
+    local temp_2_version_number="${2#v}"
+    local temp_2_major_version_number="${temp_2_version_number%%.*}"
+    local temp_2_minor_version_number="$(echo "$temp_2_version_number" | awk -F '.' '{print $2}')"
+    local temp_2_minimunm_version_number="${temp_2_version_number##*.}"
+    if [[ "$temp_1_major_version_number" -gt "$temp_2_major_version_number" ]]; then
       return 0
-    elif [[ "$RELEASE_MAJOR_VERSION_NUMBER" -eq "$CURRENT_MAJOR_VERSION_NUMBER" ]]; then
-      if [[ "$RELEASE_MINOR_VERSION_NUMBER" -gt "$CURRENT_MINOR_VERSION_NUMBER" ]]; then
+    elif [[ "$temp_1_major_version_number" -eq "$temp_2_major_version_number" ]]; then
+      if [[ "$temp_1_minor_version_number" -gt "$temp_2_minor_version_number" ]]; then
         return 0
-      elif [[ "$RELEASE_MINOR_VERSION_NUMBER" -eq "$CURRENT_MINOR_VERSION_NUMBER" ]]; then
-        if [[ "$RELEASE_MINIMUM_VERSION_NUMBER" -gt "$CURRENT_MINIMUM_VERSION_NUMBER" ]]; then
+      elif [[ "$temp_1_minor_version_number" -eq "$temp_2_minor_version_number" ]]; then
+        if [[ "$temp_1_minimunm_version_number" -gt "$temp_2_minimunm_version_number" ]]; then
           return 0
         else
           return 1
@@ -323,13 +340,13 @@ get_version() {
     else
       return 1
     fi
-  elif [[ "$RELEASE_VERSION" == "$CURRENT_VERSION" ]]; then
+  elif [[ "$1" == "$2" ]]; then
     return 1
   fi
 }
 
 download_xray() {
-  DOWNLOAD_LINK="https://github.com/XTLS/Xray-core/releases/download/$RELEASE_VERSION/Xray-linux-$MACHINE.zip"
+  DOWNLOAD_LINK="https://github.com/XTLS/Xray-core/releases/download/$INSTALL_VERSION/Xray-linux-$MACHINE.zip"
   echo "Downloading Xray archive: $DOWNLOAD_LINK"
   if ! curl -x "${PROXY}" -R -H 'Cache-Control: no-cache' -o "$ZIP_FILE" "$DOWNLOAD_LINK"; then
     echo 'error: Download failed! Please check your network or try again.'
@@ -521,7 +538,9 @@ stop_xray() {
 
 check_update() {
   if [[ -f '/etc/systemd/system/xray.service' ]]; then
-    get_version
+    get_current_version
+    get_latest_version
+    version_gt $RELEASE_LATEST $CURRENT_VERSION
     local get_ver_exit_code=$?
     if [[ "$get_ver_exit_code" -eq '0' ]]; then
       echo "info: Found the latest release of Xray $RELEASE_LATEST . (Current release: $CURRENT_VERSION)"
@@ -576,14 +595,16 @@ remove_xray() {
 show_help() {
   echo "usage: $0 [OPTION]..."
   echo 'OPTION:'
-  echo '  --remove           Remove Xray'
-  echo '  --version          Install the specified version of Xray, e.g., --version v1.0.0'
-  echo '  -c, --check        Check if Xray can be updated'
-  echo '  -f, --force        Force installation of the latest version of Xray'
-  echo '  -h, --help         Show help'
-  echo '  -l, --local        Install Xray from a local file'
-  echo '  -p, --proxy        Download through a proxy server, e.g., -p http://127.0.0.1:8118 or -p socks5://127.0.0.1:1080'
-  echo '  -u, --install-user Install Xray in specified user, e.g, -u root'
+  echo '  --remove                  Remove Xray'
+  echo '  --version                 Install the specified version of Xray, e.g., --version v1.0.0'
+  echo '  -c, --check               Check if Xray can be updated'
+  echo '  -f, --force               Force installation of the latest version of Xray'
+  echo '  -h, --help                Show help'
+  echo '  -l, --local               Install Xray from a local file'
+  echo '  -p, --proxy               Download through a proxy server, e.g., -p http://127.0.0.1:8118 or -p socks5://127.0.0.1:1080'
+  echo '  -u, --install-user        Install Xray in specified user, e.g, -u root'
+  echo '  --reinstall               Reinstall current Xray version'
+  echo "  --not-update-service      Don't change service file if it is exist"
   exit 0
 }
 
@@ -611,34 +632,50 @@ main() {
   ZIP_FILE="${TMP_DIRECTORY}/Xray-linux-$MACHINE.zip"
 
   # Install Xray from a local file, but still need to make sure the network is available
-  if [[ "$LOCAL_INSTALL" -eq '1' ]]; then
+  if [[ -n "$LOCAL_FILE" ]]; then
     echo 'warn: Install Xray from a local file, but still need to make sure the network is available.'
     echo -n 'warn: Please make sure the file is valid because we cannot confirm it. (Press any key) ...'
     read -r
     install_software 'unzip' 'unzip'
     decompression "$LOCAL_FILE"
   else
-    # Normal way
-    install_software 'curl' 'curl'
-    get_version
-    NUMBER="$?"
-    if [[ "$NUMBER" -eq '0' ]] || [[ "$FORCE" -eq '1' ]]; then
-      echo "info: Installing Xray $RELEASE_VERSION for $(uname -m)"
-      download_xray
-      if [[ "$?" -eq '1' ]]; then
-        "rm" -r "$TMP_DIRECTORY"
-        echo "removed: $TMP_DIRECTORY"
+    get_current_version
+    if [[ "$REINSTALL" -eq '1' ]]; then
+      if [[ -z "$CURRENT_VERSION" ]]; then
+        echo "error: Xray is not installed"
         exit 1
       fi
-      install_software 'unzip' 'unzip'
-      decompression "$ZIP_FILE"
-    elif [[ "$NUMBER" -eq '1' ]]; then
-      echo "info: No new version. The current version of Xray is $CURRENT_VERSION ."
-      exit 0
-    elif [[ "$NUMBER" -eq '2' ]]; then
-      echo "info: The current version is same as the specified version. The version is $CURRENT_VERSION ."
-      exit 0
+      INSTALL_VERSION="$CURRENT_VERSION"
+      echo "info: Reinstalling Xray $CURRENT_VERSION"
+    elif [[ -n "$SPECIFIED_VERSION" ]]; then
+      SPECIFIED_VERSION="v${SPECIFIED_VERSION#v}"
+      if [[ "$CURRENT_VERSION" == "$SPECIFIED_VERSION" ]] && [[ "$FORCE" -eq '0' ]]; then
+        echo "info: The current version is same as the specified version. The version is $CURRENT_VERSION ."
+        exit 0
+      fi
+      INSTALL_VERSION="$SPECIFIED_VERSION"
+      echo "info: Installing specified Xray version $INSTALL_VERSION for $(uname -m)"
+    else
+      install_software 'curl' 'curl'
+      get_latest_version
+      version_gt $RELEASE_LATEST $CURRENT_VERSION
+      local temp_number=$?
+      if [[ "$temp_number" -eq '1' ]] && [[ "$FORCE" -eq '0' ]]; then
+        echo "info: No new version. The current version of Xray is $CURRENT_VERSION ."
+        exit 0
+      fi
+      INSTALL_VERSION=$RELEASE_LATEST
+      echo "info: Installing Xray $INSTALL_VERSION for $(uname -m)"
     fi
+    install_software 'curl' 'curl'
+    install_software 'unzip' 'unzip'
+    download_xray
+    if [[ "$?" -eq '1' ]]; then
+      "rm" -r "$TMP_DIRECTORY"
+      echo "removed: $TMP_DIRECTORY"
+      exit 1
+    fi
+    decompression "$ZIP_FILE"
   fi
 
   # Determine if Xray is running
@@ -649,7 +686,7 @@ main() {
     fi
   fi
   install_xray
-  install_startup_service_file
+  ([[ "$N_UP_SERVICE" -eq '1' ]] && [[ -f '/etc/systemd/system/xray.service' ]]) || install_startup_service_file
   echo 'installed: /usr/local/bin/xray'
   # If the file exists, the content output of installing or updating geoip.dat and geosite.dat will not be displayed
   if [[ ! -f "${DAT_PATH}/.undat" ]]; then