Deepak Prasad

Manage TuneD profiles in Linux with tuned-adm: list and read profiles, apply throughput-performance, check the recommendation, verify applied settings, inspect tuned.conf inheritance, and revert cleanly.

Reset a forgotten root password on RHEL 10 from the GRUB menu with rd.break, remount /sysroot, chroot, passwd, and SELinux autorelabel before you log in again.

Learn systemd targets as boot synchronization points: get-default, set-default, isolate multi-user or graphical, rescue and emergency mode, and one-boot overrides with systemd.unit=.

Reboot, power off and shut down Linux with systemctl and shutdown. Schedule or cancel reboots, notify users, and verify the new boot.

Install Flatpak on Linux, configure remotes, search Flathub or vendor catalogs, install update and remove sandboxed apps with flatpak run, permissions, and troubleshooting.

Learn Linux file permissions and ownership: rwx for files vs directories, chmod symbolic and octal modes, chown and chgrp, umask, SUID SGID sticky bit, and permission denied diagnosis.

Learn Linux stdin, stdout and stderr redirection with >, >>, 2>&1, pipes, tee, /dev/null, here documents, PIPESTATUS and pipefail.

Learn Linux command line basics: how the shell parses commands, navigate with paths, use quoting and expansion, find help with man and --help, and practice safe identity checks before you move on to file management and …

Understand the Linux filesystem hierarchy—what /etc, /var, /usr, and /home contain—and navigate with absolute and relative paths using pwd, cd, ls, file, stat, and find.

Manage Linux users and groups with useradd, usermod, userdel, groupadd, primary and supplementary groups, account defaults, and ownership checks.

Create LVM physical volumes, volume groups, and logical volumes, format with XFS or ext4, mount by UUID, extend a VG with vgextend, and remove layers safely.

Manage Linux processes with ps, pgrep, top, jobs, signals, and systemctl. Find high-CPU tasks, inspect process states, and stop processes safely.

Configure Chrony NTP on Linux, verify time synchronization with chronyc, force clock correction, troubleshoot sync problems, and optionally serve LAN clients.

Install DVWA on Kali Linux with the native dvwa package, Docker Compose, or a manual Apache and MariaDB stack, then verify port 42001 or 4280 and fix common setup errors.

Install OWASP Juice Shop on Kali Linux using the native package, Docker, or Node.js source, then verify access, connect Burp Suite, and fix common errors.

Use kubectl cordon, drain, and uncordon to mark a node unschedulable, evict workloads safely with PodDisruptionBudget awareness, and return the node to service after maintenance.

Build a kubeadm HA control plane with stacked etcd, HAProxy and Keepalived, control-plane joins, and tested API-server and load-balancer failover.

Check Kubernetes API-server, kubectl, kubelet, kubeadm, container runtime, and control-plane versions, then compare supported version skew.

Deploy Falco on Kubernetes with Helm and modern eBPF, verify syscall collection, trigger runtime alerts, and write and tune custom rules.

Investigate a Kubernetes incident with Falco and audit logs, preserve evidence, contain workloads and nodes, rotate credentials, and redeploy safely.

Enable Kubernetes audit logging on a kubeadm API server, apply a focused policy, generate test events, and trace RBAC, Secret, exec, and denied requests.

Build immutable Kubernetes containers with digest-pinned images, read-only roots, non-root execution, dropped capabilities, and explicit writable volumes.

Promote one container image digest through Trivy scanning, SBOM archival, Cosign signing, registry copy, and Kubernetes drift verification.

Configure Istio PeerAuthentication in PERMISSIVE and STRICT modes, verify workload certificates and sidecar TLS behavior, and block plaintext clients that lack mesh identity.

Scan Kubernetes YAML with Kubesec and KubeLinter, compare findings, lint rendered Helm and Kustomize manifests, enforce CI checks, and verify remediation.

Sign and verify container images with Cosign using local keys and keyless identities, attach SPDX attestations, and test failed verification.

Configure Kubernetes ImagePolicyWebhook with an HTTPS ImageReview service, digest rules, TTL caching, and fail-open or fail-closed admission tests.

Generate CycloneDX and SPDX SBOMs with Trivy, rescan stored inventories for vulnerabilities, compare formats, and archive digest-linked release artifacts.

Build secure minimal container images with multi-stage Dockerfiles, distroless bases, non-root users, digest pins, secret mounts, and runtime checks.

Enable Cilium transparent WireGuard encryption on a running cluster, verify peers and handshake state, capture plaintext versus encrypted cross-node Pod traffic, and document what traffic stays outside the tunnel.