Помогите в создание .service

[Unit]
Description=Перерыв
#After=pulseaudio.service

[Service]
Type=oneshot
User=viktor
Group=wheel
RemainAfterExit=yes
#ExecStart=/usr/bin/xfce4-terminal -e --maximize --hide-menubar --command='zenity --entry --text="Пора на обед:"'
ExecStart=/usr/bin/xfce4-terminal -e --maximize --hide-menubar --command='whiptail --msgbox "ОБЕД!" 10 20'

#[Timer]
#OnCalendar=*-*-* 12:00:00
#Persistent=true
#OnBootSec=15min
#OnUnitActiveSec=5days
[Install]
WantedBy=multi-user.target

[root@viktor-pc viktor]# systemctl daemon-reload
[root@viktor-pc viktor]# systemctl start pereruv.service
Job for pereruv.service failed because the control process exited with error code.
See "systemctl status pereruv.service" and "journalctl -xe" for details.
[root@viktor-pc viktor]# systemctl status pereruv.service
● pereruv.service - Перерыв
   Loaded: loaded (/etc/systemd/system/pereruv.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Sun 2019-04-14 10:07:30 +05; 12s ago
  Process: 3518 ExecStart=/usr/bin/xfce4-terminal -e --maximize --hide-menubar --command=whiptail --msgbox "ОБЕД!" 10 20 (code=exited,>
 Main PID: 3518 (code=exited, status=1/FAILURE)

апр 14 10:07:30 viktor-pc systemd[1]: Starting Перерыв...
апр 14 10:07:30 viktor-pc xfce4-terminal[3518]: Unable to init server: Не удалось подключиться к: В соединении отказано
апр 14 10:07:30 viktor-pc xfce4-terminal[3518]: cannot open display:
апр 14 10:07:30 viktor-pc systemd[1]: pereruv.service: Main process exited, code=exited, status=1/FAILURE
апр 14 10:07:30 viktor-pc systemd[1]: pereruv.service: Failed with result 'exit-code'.
апр 14 10:07:30 viktor-pc systemd[1]: Failed to start Перерыв.
lines 1-12/12 (END)

[Unit]
Description=Перерыв

[Timer]
OnCalendar=*-*-* 12:00:05
Persistent=true
#Unit=/etc/systemd/system/pereruv.service
RandomizedDelaySec=15m

[Install]
WantedBy=timers.target

[root@viktor-pc viktor]# systemctl daemon-reload
[root@viktor-pc viktor]# systemctl start pereruv.timer
[root@viktor-pc viktor]# systemctl status pereruv.timer
● pereruv.timer - Перерыв
   Loaded: loaded (/etc/systemd/system/pereruv.timer; enabled; vendor preset: disabled)
   Active: active (waiting) since Sun 2019-04-14 08:58:37 +05; 1h 17min ago
  Trigger: Sun 2019-04-14 12:06:18 +05; 1h 49min left

апр 14 08:58:37 viktor-pc systemd[1]: Stopped Перерыв.
апр 14 08:58:37 viktor-pc systemd[1]: Stopping Перерыв.
апр 14 08:58:37 viktor-pc systemd[1]: Started Перерыв.
[root@viktor-pc viktor]#

Environment=DISPLAY=:0

indeviral
Environment=DISPLAY=:0