wget 錯誤:ERROR: The certificate of `url' is not trusted. 處理方式

使用wget抓檔時 如果是https，有時會出現如下錯誤：

ERROR: The certificate of `url' is not trusted.
ERROR: The certificate of `url' hasn't got a known issuer.

解決方式如下：
1.
#apt-get install ca-certificates

2.
#wget --no-check-certificate https://download/url