techjaiveer

  pwd → Show current directory ls → List files ls -l → Long listing ls -a → Show hidden files cd /home → Change directory cd .. → Go up one level mkdir test → Create directory rmdir test → Remove empty directory touch file.txt → Create empty file cp file1 file2 → Copy file mv file1 file2 → Move/rename file rm file.txt → Delete file rm -r dir → Delete directory recursively find / -name file.txt → Search file tree → Show directory tree whoami → Show current user id → Show user ID info who → Show logged-in users w → Show active users adduser user1 → Add user passwd user1 → Set password usermod -aG wheel user1 → Add user to group groups user1 → Show groups deluser user1 → Delete user su user1 → Switch user Command: lsblk Notes: Lists block devices (disks, partitions). Command: df -h Notes: Shows mounted filesystems and usage. Command: sudo fdisk -l Notes: Lists disk partitions. Command: du -sh /dir Notes: Shows total size of a directory. Com...

Q: What does VLAN stand for? A: Virtual Local Area Network. Q: Purpose of VLAN? A: To logically segment a network into smaller broadcast domains. Q: VLAN range in Cisco switches? A: 1–4094. Q: Default VLAN on Cisco switches? A: VLAN 1. Q: VLAN type used for management? A: Management VLAN. Q: VLAN type used for voice traffic? A: Voice VLAN. Q: Command to create VLAN in Cisco IOS? A: vlan <id> . Q: VLAN tagging standard? A: IEEE 802.1Q. Q: Native VLAN default ID? A: VLAN 1. Q: VLANs reduce what type of traffic? A: Broadcast traffic. Q: Can VLAN span multiple switches? A: Yes, using trunk ports. Q: VLANs improve what? A: Security and efficiency. Q: VLAN membership types? A: Static and dynamic. Q: Static VLAN assignment method? A: Manually configure port to VLAN. Q: Dynamic VLAN assignment method? A: Using VMPS (VLAN Membership Policy Server). Q: VLAN hopping attack exploits what? A: Misconfigured trunk ports. Q: VLANs separate what? A: Layer 2 broad...

  Networking 1. Difference between Hub, Switch, and Router Hub: Sends data to all devices (broadcast). Example: If PC1 sends a file, all PCs receive it, even if only PC2 needs it. Switch: Sends data only to the destination MAC. Example: PC1 → PC2 directly, no unnecessary traffic. Router: Connects different networks. Example: Your home router connects LAN to the internet. 2. OSI Model and Layers Seven layers: Physical (cables, signals) Data Link (MAC addresses, Ethernet) Network (IP addressing, routing) Transport (TCP/UDP, reliability) Session (manages sessions) Presentation (encryption, compression) Application (user interface, HTTP, SMTP) Example: Sending an email uses all layers. 3. TCP vs UDP TCP: Reliable, connection‑oriented. Example: Web browsing, email. UDP: Fast, connectionless. Example: Streaming, gaming. 4. IP Address Classes & Subnetting Class A: 1–126, large networks. Class B: 128–191, medium. Class C: 192–223, small. Subnetting: Divides a network into smal...

What is Outlook primarily used for? → Email What feature schedules meetings? → Calendar What feature stores contacts? → People What feature manages tasks? → Tasks What feature shows upcoming events? → Agenda What feature filters unwanted mail? → Junk What feature organizes mail automatically? → Rules What feature groups related emails? → Conversation What feature provides offline access? → Cached What feature integrates with Teams? → Integration What feature shows unread count? → Badge What feature highlights important mail? → Focused What feature stores attachments online? → OneDrive What feature allows multiple accounts? → Profiles What feature secures login? → MFA What is the default mail protocol for Outlook? → MAPI What protocol syncs mail with Exchange? → EAS What protocol retrieves mail? → IMAP What protocol downloads mail? → POP3 What protocol sends mail? → SMTP What feature delays sending mail? → Delay What feature recalls sent mail? → Recall What feature auto‑responds when aw...

  What does LAN stand for? → Local What does WAN stand for? → Wide What does MAN stand for? → Metropolitan What does PAN stand for? → Personal What does VPN stand for? → Virtual What does ISP stand for? → Provider What does IP stand for? → Internet What does MAC stand for? → Address What does DNS stand for? → Domain What does DHCP stand for? → Dynamic What does HTTP stand for? → Hypertext What does HTTPS stand for? → Secure What does FTP stand for? → File What does SMTP stand for? → Mail What does POP3 stand for? → Post What does IMAP stand for? → Access What does VoIP stand for? → Voice What does URL stand for? → Locator What does ARP stand for? → Resolution What does RARP stand for? → Reverse What does ICMP stand for? → Control What does SNMP stand for? → Management What does Telnet provide? → Remote What does SSH provide? → Secure What does Ping test? → Connectivity 📡 Devices & Hardware (26–50) Device connecting LAN segments → Switch Device connecting different networks → R...

What is the main role of an OS? → Management Which OS manages multiple users simultaneously? → Multiuser Which OS allows multiple tasks at once? → Multitasking Which OS runs on mobile devices? → Android Which OS is developed by Apple? → macOS Which OS is open‑source and widely used in servers? → Linux Which OS is most common on desktops? → Windows What is the kernel responsible for? → Control What is the smallest unit of CPU scheduling? → Process What is a lightweight process called? → Thread What is the purpose of scheduling? → Allocation What is the memory management technique that swaps processes? → Paging What is the memory management technique using fixed partitions? → Segmentation What is virtual memory used for? → Extension What is the file system in Windows? → NTFS What is the file system in Linux? → EXT4 What is the file system in macOS? → APFS What is the interface between user and OS? → Shell What is the command‑line interface in Windows? → CMD What is the command‑line inter...

CCNA – Cisco Certified Network Associate 200-301 Cisco Systems in 2026 is a global leader in networking, AI infrastructure, and cyber security, headquartered in San Jose, California, with about 86,000 employees and annual revenues exceeding $51 billion. It remains one of the world’s largest technology companies,  CCNA – Cisco Certified Network Associate Purpose: Entry-level certification for networking professionals. Focus: Builds foundational knowledge of networking, IP connectivity, security fundamentals, automation, and cloud basics. Who it’s for: Beginners starting a career in networking or IT support. Goal: To validate that you can install, configure, and troubleshoot small to medium-sized networks. CCNP – Cisco Certified Network Professional Purpose: Mid-level certification for advanced networking skills. Focus: Enterprise networking, routing, switching, security, automation, and collaboration. Who it’s for: Professionals with experience who want to specialize in areas...