起因   server ip 固定時間會換,無法使用dns。看能不能有方法獲得server 最新ip   思路  1.  印出ip  2. 串slack  3. 排程   最終成果   ip.sh   MSG=`ifconfig  | grep -E 'inet.[0-9]' | grep -v '127.0.0.1' |awk '{print $2}'`  CHANNEL="#serverip" USERNAME="Server" EMOJI=":ghost:" PAYLOAD="payload={\"channel\": \"$CHANNEL\", \"username\": \"$USERNAME\", \"text\": \"$MSG\", \"icon_emoji\": \"$EMOJI\"}" HOOK=https://hooks.slack.com/services/XXXXXX/BOOOOOO/n2345566 curl -X POST --data-urlencode "$PAYLOAD" "$HOOK"   建立排程檔  com.postip.plist   <?xml version="1.0" encoding="UTF-8"?>  <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">  <plist version="1.0">  <dict>   <key>Label</key>   <string>com.postip.plist</string>   <key...