Linux Commands

Linux Commands

1. RPM Version Info:

   • rpm -qa foo

2. Shutdown X11:

   • init 3

3. Reboot the System:

   • init 6

4. Mount a CDROM:

   • mount /dev/cdrom

5. Unmount a CDROM:

   • umount /dev/cdrom

6. List Start Up Scripts:

   • chkconfig --list

7. Turn On Start Up Script:

   • chkconfig service start

8. Turn Off Start Up Script:

   • chkconfig service off

9. Get the kernel version by typing

   • uname -r

10. Format USB Device to Vfat

    •  mkfs.vfat -F 32 /dev/sda1

11. How to create tarball's assuming your directory is called foo:

    • tar -cvzf foo.tar.gz /dir/foo

12. Add user to Virtual Postfix Database:

    • postmap virtual

13. Reload Postfix:

    •  postfix reload

14. Produces Postfix Queue List:

    •  postqueue -p

15. Also Produces Postfix Queue List:

    • mailq

16. Flush Postfix Queues:

    •  postqueue -f

17. Remote Desktop for Windows (toggle -f on or off for fullscreen):

    • rdesktop -g 1152x768 -a 24 -b -f mail

18. Unzip bz2 files:

    • bzip2 -cd files.tar.bz2 | tar xvf -

19. Show program install path:

    • which {program}

20. Removes mail from mail queue

    • postsuper -d {queue id}>

21. Displays Hardware info from BIOS (must have installed dmidecode installed)

    • dmidecode

22. To get a Network list of current IP/Hostname's, type the following on the command line:

    • dig axfr hosthame

23. or to sort by IP type:

    • dig axfr hostname |grep IN | egrep A |sort -n  -k 5 -k 7 -t .

24. Type the following to setup rpmq to find true kernel version

    • alias rpmq='rpm --qf '\''%{NAME}-%{VERSION}-%{RELEASE}.%{ARCH}\n'\'' -q'

25. Type the following to determine the kernel version

    • rpmq kernel

26. List all PCI Devices:

    • lspci

27. Reload named:

    • rndc reload

28. Create Database:

    • create database {DATABASE NAME};

29. Create Database Privileges:

    • grant all privileges on {DATABASE NAME}.* to {DATABASE USER}@localhost identified by '{DATABASE PASSWORD}';

30. Set Privileges:

    • flush privileges;

31. Netstat IP,PORTS

    • netstat -tnap

32. Create QEMU Disk Images:

    • qemu-img create -f qcow {name}.img 3G

33. Install OS on QEMU Drive Image via CD-ROM

    • qemu -cdrom /dev/cdrom -hda {name}.img -m {memsize} -boot d

34. Install OS on QEMU Drive Image via IMAGE

    • qemu -cdrom {name}.iso -hda {name}.img -m {memsize} -boot d

35. Run QEMU Disk Images with Sound (Blaster16):

    • qemu -hda {name}.img -m {memsize} -soundhw es1370 -localtime

36. Move seamless between host and guest

    • qemu -hda {name}.img -m {memsize} -soundhw es1370 -localtime -usb -usbdevice tablet

37. Resize AVI Files (--export_asr 3 is widescreen and --export_asr 2 is fullscreen)

    • transcode -i INPUT.avi -y ffmpeg,ffmpeg -F mpeg4 -Z 320x,fast --export_asr 2 -o OUTPUT.avi -E 44100,16,2 -b 256

38. Start NetworkManager GUI Applet

    • nm-applet &

39. Set Password for MySQL Root

    • mysqladmin -u root password new-password

40. Remove User account and Home dir

    • userdel -r {username}

41. Mount an ISO image

    • mount -o loop -t iso9660 filename.iso /mnt/iso

42. Create random passwords

    • head /dev/urandom | strings

43. Show partions on a drive

    • sfdisk -l

44. You want to download all the GIFs from an HTTP directory. The command 'wget http://host/dir/*.gif ' doesn't work, since HTTP retrieval does not support globbing. In that case, use:

    • wget -r -l1 --no-parent -A.gif http://host/dir/

45. How to rsync

rsync -r -a -v -e "ssh -l {username}" --delete {remote machine}/dir /dir