Learn, Solve & Master Python, Linux, SQL, ML & DevOps
Fix Shell Script “Permission Denied” Error
Make scripts executable and fix Windows line endings.
Category Linux Solutions
Add User to Sudoers Safely
Grant sudo using visudo or wheel group without breaking sudoers.
Fix “Device is Busy” Error when Unmounting
Use lsof/fuser to find processes and safely unmount.
Check Which Process Is Using a Port
Find process blocking ports using ss, netstat, or lsof.
How to Mount an ISO File in Linux
Mount ISO images on loop device and access contents.
Fix: Cannot find a valid baseurl in yum/dnf
Resolve broken repo URL, DNS, or network issues for yum/dnf.
Reset Forgotten Root Password (rd.break method)
Use GRUB rd.break to reset the root password safely.
Extend LVM Partition Without Downtime (Adding New Disk / PV)
Add PV, extend VG and LV and grow filesystem online.
Fix Slow SSH Login (GSSAPI Authentication Delay)
SSH login pauses due to GSSAPI/Kerberos authentication.