IMPORTANT LINUX COMMANDS

#linux #mounting #partitioning #filesystems #disk

1. To modify the superblock reserve space # tune2fs -m <give space how much you want> <partition name>
2. To check the consistency of the filesystem# fsck <partition name>
3. To check the consistency of the filesystem in interactive mode# e2fsck <partition name>
4. To check the consistency of the filesystem without interactive mode# e2fsck -p <partition name>
5. To see the superblock information of a partition in Linux# mke2fs -n <partition name>
6. To format the partition in the specified filesystem type# mke2fs -t <file system type> <partition name>
7. # umount -a -> to unmount all the file systems except the root(/) file system
8. # mount -a -> to mount all the file systems which are configured in /etc/fstab file
9. # fsck -A -> to run fsck on all filesystems
10. # umount <file system mount point> -> to unmount the file system
11. # fdisk -l -> to list all the disks in your filesystem
12. # mount -o remount,rw /dev/sda1 -> to mount the partition with read and write permissions
13. # fuser -cu <partition/device name> -> to see the users who are accessing that file system.
14. # fuser -cK <partition/device name> -> to kill the users processes who accessing the filesystem.
15. # journalctl -> It tracks all the log files between two different timings and by default saved in /run/log location.* /run/log - is mounted on tmpfs file system. i.e., if the system is rebooted, the whole information in the location will be deleted.
16. # umount -f <mount point> -> to unmount the device/partition forcefully
17. # df -hT -> It shows the all information about the filesystem like type, size, how much is used and mount points, etc..
18. # mount or # cat /etc/mtab -> to list all the mount points in filesystem.
19. # free -m -> It will show the present swap size
20. # swapon -s -> to see the swap usage
21. # fdisk <disk name> -> To make the new partition in a particular disk.
22. # mount -l -> To list all the mounted partitions along with their labels.
23. # e2label <device/partition name> -> To assign the labels to the partitions.
24. # ncdu - > It means 'NCurses Dick Usage', It will list the biggest file and directories.
25. du -h -> It will show the dick usage of all files in the file system.
26. mkfs.ext4/ext3/xfs/vfat <device name> -> To make file system in linux.* Here 'ext4/ext3/xfs/vfat' are all filesystem formats.
27. #du -s * | sort -nr | head -n10 -> This command shows the biggest directories from that filesystem.
28. # sar -> sat utility is to watch the system activity report like CPU, memory,...etc
29. # auditctl -> To check the audit report of the system.
30. # smartctl -H <disk name> -> To check the health of the specified hard disk.