Systemd 為了安全性因素, 預設 PrivateTmp=true
即每個 Service 都有自己的 /tmp,
真實位置是存在於像這樣的路徑 /tmp/systemd-private-291a89c46ea14fa282e95374a841ec4e-httpd.service-eYQNRI/tmp
例: 將 Apache 停用 PrivateTmp
sed -i s/PrivateTmp=true/PrivateTmp=false/ /lib/systemd/system/httpd.service
systemctl daemon-reload
systemctl restart httpd
