TECHNICAL INTERVIEW QUESTIONS ON UNIX/LINUX

1. How do you list the files in an UNIX directory while also showing hidden files? ls -ltra

2. How do you execute a UNIX command in the background? Use the “&”. for eg : cp file1 file2 &

3. What UNIX command will control the default file permissions when files are created? umask

4. Explain the read, write, and execute permissions on a UNIX directory. Read allows you to see and list the directory contents. Write allows you to create, edit and delete files and subdirectories in the directory. Execute gives you the permissions to run programs or shells from the directory.

5. What is the difference between a soft link and a hard link? A symbolic (soft) linked file and the targeted file can be located on the same or different file system while for a hard link they must be located on the same file system.

6. Give the command to display space usage on the UNIX file system. df -lk

7. Explain iostat, vmstat and netstat. iostat reports on terminal, disk and tape I/O activity. vmstat reports on virtual memory statistics for processes, disk, tape and CPU activity. netstat reports on the contents of network data structures.

8. How would you change all occurrences of a value using VI? %s/(old value)/(new value)/g

9. Give two UNIX kernel parameters that effect an Oracle install. SHMMAX & SHMMNI

10. Briefly, how do you install Oracle software on UNIX? Basically, set up disks, kernel parameters, and run orainst.

11. Q: What is the way to view a unix network share on a Windows computer, within explorer ?
NFS, The Unix computer can be running a NFS Server Daemon.

12 . In Unix OS, what is the file server?
The file server is a machine that shares its disk storage and files with other machines on the network.

13. What is LILO?
LILO stands for Linux boot loader. It will load the MBR, master boot record, into the memory, and tell the system which partition and hard drive to boot from.

14. What is NFS? What is its job?
NFS stands for Network File System. NFS enables filesystems physically residing on one computer system to be used by other computers in the network, appearing to users on the remote host as just another local disk.

15. What is HTTP Tunneling ?
HTTP Tunneling is a security method that encryptes packets traveling throught the internet. Only the intended reciepent should be able to decrypt the packets. Can be used to Create Virtual Private Networks. (VPN)