diff --git a/lib/tasks/install_certbot.rake b/lib/tasks/install_certbot.rake
index d208464..822a90c 100644
--- a/lib/tasks/install_certbot.rake
+++ b/lib/tasks/install_certbot.rake
@@ -36,31 +36,51 @@ namespace :create_site do
             Net::SSH.start(@site_server.ip , @site_server.account , password: @site_server.password) do |ssh|
               certbot_path = exec_ssh_command_by_sudo_and_see_output(ssh,"bash -l -c 'which certbot'",false,true).strip
               snap_path = exec_ssh_command_by_sudo_and_see_output(ssh,"bash -l -c 'which snap'",false,true).strip
+              already_apt_update = false
               if certbot_path.blank?
                 update_thread_infos("checking kernel version")
                 kernel_version = exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' uname -r",false,true).strip.to_f rescue 0.0
                 update_thread_infos("kernel_version: #{kernel_version}")
                 if kernel_version < 4.4
-                  raise "Kernel version need upgrade to >= 4.4(snap need kernel >= 4.4)"
-                end
-                if snap_path.blank?
+                  update_thread_infos("Downloading certbot by using python3(since kernel < 4.4)...")
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' add-apt-repository ppa:deadsnakes/ppa -y",false)
                   update_thread_infos("execing apt update...")
                   exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' apt-get -y -o DPkg::options::='--force-confdef' -o DPkg::options::='--force-confold' update",true,false)
-                  update_thread_infos("Installing snap...")
-                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' apt install snapd -y",true,false)
-                  snap_path = exec_ssh_command_by_sudo_and_see_output(ssh,"bash -l -c 'which snap'",false,true).strip
-                end
-                if snap_path.present?
-                  update_thread_infos("Installing snap core...")
-                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' bash -l -c 'snap install core && snap refresh core'",true,false)
-                  update_thread_infos("Installing certbot with snap...")
-                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' snap install --classic certbot",true,false)
-                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' ln -s /snap/bin/certbot /usr/bin/certbot",false,false)
-                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' certbot register --email bohung@rulingcom.com --agree-tos -n",false,false)
+                  already_apt_update = true
+                  update_thread_infos("Installing python3.6 python3.6-venv libaugeas0 ...")
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' apt-get install python3.6 python3.6-venv libaugeas0 -y",false)
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' rm -rf /opt/certbot/",false)
+                  update_thread_infos("generating venv for certbot ...")
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' python3.6 -m venv /opt/certbot/",false)
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' /opt/certbot/bin/pip install --trusted-host pypi.python.org --upgrade pip",false)
+                  update_thread_infos("Installing certbot on python3.6 ...")
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' /opt/certbot/bin/pip install --trusted-host pypi.python.org certbot certbot-nginx",true)
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' rm -f /usr/bin/certbot",true)
+                  exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' ln -s /opt/certbot/bin/certbot /usr/bin/certbot",true)
                   update_thread_infos("Finish install certbot!")
                   certbot_path = "/usr/bin/certbot"
                 else
-                  update_thread_infos("There was some error when installing snap!")
+                  if snap_path.blank?
+                    unless already_apt_update
+                      update_thread_infos("execing apt update...")
+                      exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' apt-get -y -o DPkg::options::='--force-confdef' -o DPkg::options::='--force-confold' update",true,false)
+                    end
+                    update_thread_infos("Installing snap...")
+                    exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' apt install snapd -y",true,false)
+                    snap_path = exec_ssh_command_by_sudo_and_see_output(ssh,"bash -l -c 'which snap'",false,true).strip
+                  end
+                  if snap_path.present?
+                    update_thread_infos("Installing snap core...")
+                    exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' bash -l -c 'snap install core && snap refresh core'",true,false)
+                    update_thread_infos("Installing certbot with snap...")
+                    exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' snap install --classic certbot",true,false)
+                    exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' ln -s /snap/bin/certbot /usr/bin/certbot",false,false)
+                    exec_ssh_command_by_sudo_and_see_output(ssh,"sudo -p 'sudo password:' certbot register --email bohung@rulingcom.com --agree-tos -n",false,false)
+                    update_thread_infos("Finish install certbot!")
+                    certbot_path = "/usr/bin/certbot"
+                  else
+                    update_thread_infos("There was some error when installing snap!")
+                  end
                 end
               end
               if certbot_path.present?