Linux Troubleshooting with SadServer

#Linux #RHCSA #DevOps #SystemAdmin #LinuxBasics #BootProcess #Learning #ITSkills #Linux #RHCSA #RedHat #SystemAdministration #DevOps #LinuxCommands #ITInfrastructure #CyberSecurity #CloudComputing #LearningJourney 🚀 Linux Booting Process — >>>> 🔌 1. Power ON When you press the power button, the system firmware starts. 🖥️ 2. BIOS / UEFI Performs POST (Power-On Self Test) Checks hardware: CPU, RAM, keyboard, disk Searches for a bootable device 💽 3. Bootloader (GRUB) GRUB (Grand Unified Bootloader) is loaded Displays OS selection menu Loads: ✔ Kernel (vmlinuz) ✔ initramfs (initrd) 🧠 4. Kernel Core of Linux (brain of the system) Initializes hardware and drivers Mounts temporary root filesystem (initramfs) 📦 5. initramfs Temporary filesystem Loads required drivers Locates and mounts the real root filesystem ⚙️ 6. systemd (PID 1) First process started by kernel Manages system initialization Starts all services and processes 🎯 7. Target (Runlevel) systemd switches to a target: multi-user.target → CLI mode graphical.target → GUI mode 🔧 8. Services Start Network SSH Cron Firewall Logging services 🖥️ 9. Login Screen CLI or GUI login prompt appears System is ready to use ✅ 📌 Quick Flow (Easy to Remember): 👉 Power → BIOS → GRUB → Kernel → initramfs → systemd → Services → Login 💡 Important Commands: ps -p 1 # Check first process (systemd) uname -r # Kernel version systemctl get-default journalctl -b # Boot logs 🎯 Interview Highlights: ✔ First process → systemd (PID 1) ✔ Bootloader → GRUB ✔ Kernel → Core of Linux ✔ Boot issues → GRUB / Kernel / Filesystem Master this flow and you’ll handle both interviews and real-world troubleshooting with confidence 💪 #Linux #RHCSA #DevOps #SystemAdmin #LinuxBasics #BootProcess #Learning #ITSkills #Linux #RHCSA #RedHat #SystemAdministration #DevOps #LinuxCommands #ITInfrastructure #CyberSecurity #CloudComputing #LearningJourney

245 pages on the Linux terminal. Free PDF, no signup. Came across this one by Dargslan. Solid resource for anyone living in the shell. What's inside: • 16 chapters: shell basics to advanced scripting • Bash script templates ready to reuse (monitoring, backup, log analysis) • Permissions, cron, networking, process management • Linux vs Windows command comparison • Real troubleshooting walkthroughs, not just theory Good fit for DevOps engineers, SREs, platform folks, or anyone who SSHs into servers daily. What's the first command you'd teach someone new to Linux?

Some people really think knowing docker run and docker exec is enough to call themselves DevOps. Then the app can’t reach the database and suddenly its: "maybe restart the container?" Bro.. do u even know how the traffic gets there in the first place ?!!! The scary part is tools became so easy that people skip the fundamentals completely: networking, Linux, infra, storage, DNS, routing, debugging.. They know how to use the abstraction, not what the abstraction is hiding. #DevOps #Docker #Kubernetes #Linux #CloudComputing #PlatformEngineering #SRE #Networking #Infrastructure #CloudNative #SysAdmin #TechHumor #SoftwareEngineering #Backend #Programming #AWS #OpenToWork #TechCommunity

Most developers don’t fail because they lack skill. They fail because they repeat everything… manually 🤔 10 servers. Same setup. SSH. Command. Repeat. Again. Again. Again. 🔁 That’s not engineering. That’s punishment. 😈 Ansible changes the game. 🦸🏼 One playbook. One command. Every server configured at once. 👌 If you’re still doing things manually… you’re already behind. Start automating on a real server → https://www.ssdnodes.com/ #ansible #devops #automation #linux #sysadmin #cloudcomputing #vps #webhosting #infrastructure #programming #developer #codinglife #nginx #ssh #terminal #itcareer #learncoding #techtok #buildinpublic #cloudhosting #servers #backend #fullstack #softwareengineering #deploy

📌 Linux Boot Process & Password Recovery 🔐🚀 Hello Connections, Today I revised some important Linux administration concepts that are commonly asked in interviews and useful in real-time troubleshooting. 🔹 Linux Boot Process 1️⃣ BIOS / UEFI 👉 Performs POST (Power-On Self-Test) and checks hardware 2️⃣ GRUB Bootloader 👉 Loads the Linux kernel into memory 3️⃣ Kernel Initialization 👉 Initializes hardware, memory, and drivers 4️⃣ systemd / init 👉 Starts background services and system processes 5️⃣ Login Prompt 👉 User gets terminal or GUI login access 🔹 Password Recovery in Linux Scenario: Forgot root/user password ✔️ Restart the system ✔️ Open GRUB menu ✔️ Boot into rescue/emergency mode ✔️ Remount filesystem with write permissions ✔️ Reset password using: "passwd username" 🔹 Related Important Concepts ✔️ Rescue Mode ✔️ Single User Mode ✔️ Root Privileges ✔️ GRUB Security 💡 Understanding boot process and password recovery helps in Linux troubleshooting and system administration tasks. Currently improving my Linux administration and troubleshooting skills every day 🚀 #Linux #RHCSA #SystemAdmin #DevOps #InterviewPrep #Learning #Fresher

🐧 Linux Zombie Process — Real Production Troubleshooting Topic While monitoring Linux servers in production, you may sometimes notice processes in: Z (Zombie) state ✅ What is a Zombie Process? A zombie process is a process that has: ✔ Completed execution ✔ But still has an entry in the process table This happens when: 👉 Parent process does not properly collect the child process exit status. Check using: ps -ef | grep defunct Or: top Example Output: 1234 1 0 ? 00:00:00 [java] <defunct> Common Causes: 🔹 Application bugs 🔹 Improper process handling 🔹 Parent process failure 🔹 Long-running background jobs Why is it dangerous? Few zombie processes → Usually manageable Too many zombie processes → Process table exhaustion This can eventually impact: ❌ Application stability ❌ New process creation ❌ System performance Troubleshooting Steps: ✅ Identify parent process (PPID) ps -o ppid= -p <PID> ✅ Restart parent process if required ✅ Kill/restart faulty application ✅ Monitor recurring process creation Important Note: Zombie processes do not consume CPU or memory significantly, but large numbers can become a serious production issue. This is a commonly discussed Linux troubleshooting topic in experienced-level DevOps interviews. #Linux #DevOps #ProductionSupport #AWS #Kubernetes #SRE #CloudComputing #SystemAdministration #Monitoring

𝐃𝐚𝐲 𝟒8 = 𝐋𝐢𝐧𝐮𝐱 𝐒𝐞𝐫𝐢𝐞𝐬 =𝐇𝐨𝐰 𝐝𝐨 𝐲𝐨𝐮 𝐡𝐚𝐧𝐝𝐥𝐞 𝐮𝐬𝐞𝐫 𝐚𝐧𝐝 𝐠𝐫𝐨𝐮𝐩 𝐜𝐥𝐞𝐚𝐧𝐮𝐩 𝐢𝐧 𝐲𝐨𝐮𝐫 𝐞𝐧𝐯𝐢𝐫𝐨𝐧𝐦𝐞𝐧𝐭? 𝐃𝐨 𝐲𝐨𝐮 𝐮𝐬𝐞 𝐚𝐮𝐭𝐨𝐦𝐚𝐭𝐢𝐨𝐧 𝐬𝐜𝐫𝐢𝐩𝐭𝐬 𝐨𝐫 𝐬𝐭𝐢��𝐤 𝐭𝐨 𝐭𝐡𝐞 𝐂𝐋𝐈? 𝐋𝐞𝐭’𝐬 𝐝𝐢𝐬𝐜𝐮𝐬𝐬.! Manageing multiple users by using groups is very essential part in linux right. In the same way, deleting unwanted groups is much more important in linux. In my latest youtube shorts, I explained how safely delete the groups in linux. Please go through it once. At first, let's know where and your recent groups will store. For that we have file called /etc/group. ✅ vim /etc/group ✅ tail -n 5 /etc/group => Which prints last 5 lines of a file. ✅ Run groupdel <group_name> to remove the group from the system instantly. 🤝 Check out the full demonstration here: https://lnkd.in/gk7fTPic 📍 Follow for more Daily Linux Commands and Master it #Linux #LinuxCommands #Devops #LinuxShellScripting #AWSCloud #Cli #LinuxAdmin #LinuxTutorial #ubuntu #Centos #RHEL #DevopsTools #TechContent #Freshers #Jobs #Automation #LinuxServers #TechTutorials #CloudEngineering #CareerInTech #SystemAdministration #groupdelCommand #DailyLinux

DevOps Zero to Job-Ready – Day 24/180 | System Info Script Understanding the current state of a server is one of the most important Linux skills. Commands like `uname`, `free`, `df`, and `ps` help inspect CPU, memory, uptime, and disk usage quickly. A good engineer should be able to assess server health within minutes after login. Today’s focus was building a script that generates a quick system health report. More structured DevOps notes and scenarios available on www.engidock.com Next: Network troubleshooting basics #DevOps #Linux #SRE #EngiDock

Day 4 of my Cloud Engineering Journey  Today I learned about Linux process management and how processes are monitored and controlled in the terminal. Practiced commands like: ps ps aux ps -ef ps aux | nl ps aux | wc -l ps aux | grep java kill PID kill -9 PID kill -STOP PID kill -CONT PID renice -n 10 -p PID Also understood: What a PID (Process ID) is Viewing running processes Checking CPU and memory utilization Filtering specific processes using grep Forcefully stopping processes Temporarily pausing and resuming processes Changing process priority using renice Learning how Linux manages system processes step by step  #Linux #CloudComputing #AWS #DevOps #LearningJourney

🚀 Linux Interview Questions and Answers — Part 3 🔹 11. What is the cd command? Used to change directories. Example: cd /home cd .. --- 🔹 12. What is the mkdir command? Creates directories. Example: mkdir test_folder --- 🔹 13. What is the rm command? Deletes files or directories. Examples: rm file.txt rm -r folder/ --- 🔹 14. What is the cp command? Copies files or directories. Example: cp file1.txt file2.txt --- 🔹 15. What is the mv command? Moves or renames files. Example: mv file.txt newfile.txt --- Stay connected with us: 🌐 Website https://www.CareerDream.in 🎥 YouTube https://lnkd.in/gfwz2Pg6 📢 WhatsApp Channel https://lnkd.in/g3jVSK3S 🔗 LinkedIn https://lnkd.in/gFhQEQZm @DataDog @IBM @MicrosoftAzure @GoogleCloudPlatform #LinuxServer #LinuxSystem #Unix #UnixAdmin #BashScripting #CommandLine #Terminal #DevOpsLife #CloudEngineering #SiteReliability #SRE #Kubernetes #Docker #Containerization #CI_CD #AutomationTools #InfrastructureAsCode #Ansible #Terraform #Monitoring #Logging #CyberSecurity #InfoSec #Networking #TechSkills #LearnLinux #EngineeringLife #DeveloperTools