筆者自高中二年級之後就開始在學承電腦上Java課程，因為自己本身有在使用Linux，所以非常了解Java語言跨平台的好處，自從接觸Java程式語言之後就愛上了它，之後還陸續買了許多本Java的書籍。後來拿到了TQC+的Java程式設計專業人員認證，覺得應該要再來拿拿Oracle的原廠認證，好跟國際接軌，便報考了Java 8的Oracle Certified Associate和Oracle Cer...

Windows 10已經出來有很長一段時間了，可是還是有許多人卻還在使用好幾年前的Windows 7(Windows 8使用者倒是很多都很乾脆的直接升級了)。筆者雖然自己沒有在用Windows作業系統，但其實還是蠻推薦Windows 7的使用者升級到Windows 10，原因就是Windows 10在開機速度、記憶體管理、還有安全性上有很大程度的的改善。可是好像常常會聽到Windows 10當機的...

在寫程式的時候常常會需要進行一些隨機的動作，來增加程式的娛樂性和複雜性。在Java程式語言中，可以使用Math類別的random方法或是Random物件來達到取得隨機數字的目的。取得隨機數字之後還需要撰寫一些程式來使用這個隨機數，這類程式常會頻繁地重複撰寫，十分麻煩。為了精簡程式，MagicRandom實作好了一些常用的隨機資料程式，只要使用一個靜態方法就可以完成大部分的事。

Which of the following commands connects to the remote host example.com which has OpenSSH listening on TCP port 2222? (Choose TWO correct answers.) A. ssh --port 2222 example.com B. ssh -p 2222 examp...

On a Linux system with shadow passwords enabled, which file in the file system contains the password hashes of all local users? (Specify the full name of the file, including path.)

Which of the following commands can be used to limit the amount of memory a user may use? A. umask B. usermod C. ulimit D. passwd E. chage

What is a purpose of an SSH host key? A. It must be sent by any SSH client in addition to a user key in order to identify the client's host. B. It provides the server's identity information to connec...

Which of the following commands preloads and manages keys that are used for automatic authentication while logging in to other machines using SSH? A. sshd B. ssh-agent C. ssh-keygen D. ssh-add

Which file contains a set of services and hosts that will be allowed to connect to the server by going through a TCP Wrapper program such as tcpd? (Specify the full name of the file, including path.)

Which file lists which users can execute commands using sudo? (Specify the full name of the file, including path.)