Troubleshooting disk issues in Linux requires various commands and checks. Here are some important Linux commands for disk troubleshooting

1. **Check Disk Space:** Use `df -h` to check the disk space usage on all mounted partitions.

2. **Check Disk Usage:** Use `du -h` to check the disk usage of specific directories.

3. **Check Disk Health:** Use `smartctl` to check the SMART status of a disk, e.g., `smartctl -a /dev/sda`.

4. **Check Disk Partitions:** Use `fdisk -l` or `parted -l` to list disk partitions and their details.

5. **Check Filesystem Integrity:** Use `fsck` to check and repair filesystem errors. Run it on unmounted partitions, e.g., `fsck /dev/sda1`.

6. **View Disk I/O:** Use `iotop` to view disk I/O in real-time.

7. **Check Disk Errors:** Check the `/var/log/syslog` or `/var/log/messages` file for disk-related error messages.

8. **Mount/Unmount Disks:** Use `mount` and `umount` to manually mount and unmount filesystems.

9. **Disk Performance Monitoring:** Use `iostat` to monitor disk performance and I/O statistics.

10. **Check Disk Temperature:** Use `hddtemp` or `smartctl -a` to check the temperature of a disk.

11. **List Mounted Filesystems:** Use `mount` to list currently mounted filesystems.

12. **Check Disk Space Usage per Directory:** Use `ncdu` (if installed) to interactively analyze disk usage per directory.

13. **Check Disk Read/Write Speed:** Use `hdparm` to test disk read and write speeds, e.g., `hdparm -tT /dev/sda`.

14. **Check Disk UUID:** Use `blkid` to list the UUIDs of disk partitions.

15. **Check Disk Permissions:** Ensure that permissions are set correctly for directories and files on the disk.

16. **Check for Bad Blocks:** Use `badblocks` to scan for and mark bad blocks on a disk, e.g., `badblocks -s /dev/sda`.

17. **Unmount Stuck Disk:** Use `fuser` and `lsof` to find processes using a mounted disk and then unmount it.

18. **Disk Partitioning:** Use `fdisk` or `parted` to create, delete, or resize disk partitions.

19. **Disk Benchmarking:** Use tools like `dd` or specialized benchmarking software to test disk performance.

20. **Backup and Restore:** Regularly backup important data and use tools like `tar` or `rsync` for data backup and restoration.

#DiskIssues, #DiskTroubleshooting, #FileSystem, #DiskHealth, #StorageManagement, #SMARTStatus, #FilesystemErrors, #DiskPerformance, #DataRecovery, #DiskMaintenance, #DiskMonitoring, #DiskPartitions, #FilesystemRepair, #DiskErrors, #IOTop, #DiskSpace, #BadBlocks, #DiskTemperature, #BackupAndRestore, #DiskBenchmarking

Shell script: Using FOR loop

Here's a simple shell script to print numbers using for loop.

Just got through:

# cat test.sh

for ((i=0;i<=10;i++))
do

 echo $i

done


Output: