Module 3: Configuring Interfaces and Switches PDF

Module 3 Configuring Interfaces and Switches 1 Learning Objectives Deploy networking devices. Explain network interfaces. Deploy common Ethernet switching features. Troubleshoot transceiver switching issues....

Module 3 Configuring Interfaces and Switches 1 Learning Objectives Deploy networking devices. Explain network interfaces. Deploy common Ethernet switching features. Troubleshoot transceiver switching issues. 2 Lesson 3.1 Network Interfaces 3 Think About It: Network Interfaces What is a network interface? 4 Network Interface Cards A network interface card (NIC): Transceiver component Connects the host to a transmission medium (wired or wireless) Can have multiple ports on same card Has a unique MAC address Operates at the Data Link layer 5 Symptoms of NIC Issues Common symptoms of NIC issues include: Network connectivity failure Slow network speeds Intermittent connectivity Device manager error messages Network setting error messages 6 Modular Transceivers Modular transceivers Terminate multiple types of cable and connector types Operate at the Data Link layer 7 Symptoms of Transceiver Issues Mismatched ports No link Intermittent connection loss Signal strength Intermittent connections Packet loss Poor network performance 8  Ethernet Frame Format Preamble SFD Destination Source Ether Type Payload FCS (7 Bytes) (1 Byte) MAC MAC (2 Bytes) (46-1500 (4 Bytes) (6 Bytes) (6 Bytes) Bytes) Synchronization Signals the Protocol of Error- sequence start of the Address of Address of the the payload Data being checking frame the recipient sending transmitted code device device 9 MAC Address Format Device ID Organizationally unique identifier (based on device model and (OUI) manufactured date) 2D:45:19:87:C8:E2 48-bit alphanumeric identifier; pairs of hexadecimal digits separated by colons or hyphens 10  MAC Broadcast Address Preamble SFD Destination Source Ether Type Payload FCS MAC MAC Synchronization Signals the Protocol of Data being Error- sequence start of the Address of Address of the the payload transmitted checking frame the recipient sending code device device Broadcast Address 11:11:11:11:11:11 If MAC address is all 1s, all hosts on that network will receive and process the packet 11 Lesson 3.2 Ethernet Switches 12 Hubs Hub To: D From: A Not Not Mine! Mine. Mine. A B C D Hubs send transmissions from one port to every other port. 13 Bridges Bridges separate physical network segments while keeping all nodes in the same logical network. 14 Switches Switch To: D From: A A B C D A switch sends transmissions from one port only to the destination port. 15 Ethernet Switch Types Unmanaged Modular vs. Desktop vs. Stackable vs. Managed Fixed Rack Modular can be Managed configured with Can be Desktop switches switches can be different connected are free standing configured numbers and together types of ports Unmanaged Rack-mounted Fixed come with switches have no switches are Can be managed a set number of configuration designed fit into as a single unit ports options networking racks 16 Activity: Matching Hub Switch Bridge Improves network efficiency by dividing it into smaller, manageable sections 17 Activity: Matching Hub Switch Bridge Operates by creating a single shared communication path between multiple devices in a network 18 Activity: Matching Hub Switch Bridge Intelligently directs data to a specific port based on MAC addresses, reducing network congestion 19 Activity: Matching Hub Switch Bridge Operates primarily at the physical layer 20 Activity: Matching Hub Switch Bridge Learns the MAC addresses of devices connected to it and uses this information to forward data only to the intended recipient 21 Lesson 3.3 Switch Port Configuration 22 Link Aggregation/NIC Teaming Link aggregation Combining 2+ separate cabled links into a single logical channel Provides redundancy Cost effective 23 Maximum Transmission Unit Standard ethernet frame Maximum transmission unit (MTU) is 1,500 bytes Jumbo frame Supports payload up to 9.216 bytes Reduces the number of frames transmitted Limited because they break Ethernet standards 24 Spanning Tree Protocol Spanning Tree Protocol (STP) Layer 2 protocol Prevents bridge loops Provides fault tolerance 25 Power Over Ethernet Power over Ethernet (PoE) Allows 1 cable to transmit both data and power to networked devices Simplifies network installation and expansion 26 Activity: Scavenger Hunt Find devices that use Power over Ethernet (PoE). Explore to find any devices that might be powered through an Ethernet cable. Note the device type, device location, and how it benefits from PoE 27 Lesson 3.4 Switch Troubleshooting 28 Hardware Failure Issues Hardware Failure Issue Troubleshooting and Mitigation Steps Power issues Verify stable power supply Install UPS and secondary power sources Network adapters Check for damaged ports or connectors Test with alternative adapter if possible Update or reinstall drivers Switches/routers/modems Visually inspect for damage Inspect indicator lights Verify power supply and cabling connections Restart the device following proper protocols Overheating Check for proper ventilation around the device Clean dust from intake or exhaust vents Ensure cooling systems are operational 29 Port Status Indicators Solid green The link is connected, but there is no traffic Flickering green The link is operating normally (with traffic). The blink rate indicates the link speed No light The link is not working, or the port is shut down Solid amber The port is blocked by the spanning tree algorithm Blinking amber A fault has been detected 30 Switch Show Commands Show config Device's current configuration Configuration device will use Show startup-config upon the next restart Active configuration currently Show running-config used by the device Detailed information about the Show interface device's network interfaces 31 Switch Show Command Status Down/down Both the layer 1 (physical) and layer 2 (data link) connections are inactive. Administratively down/down The interface has been manually disabled by an administrator using the shutdown command Down/error disabled The interface has been automatically disabled due to a network error or policy violation Up/down (suspended) The physical layer is operational, but the data link layer is inactive due to administrative settings or errors 32 Interface Error Counters Link state Checks if interface is up or down Immediate alert for downtime Resets Count of manual and automatic restarts High frequency of resets should be monitored Discards/drops Causes by checksum errors, mismatched MTUs, size anomalies, high load, ACL or VLAN configuration errors Used for troubleshooting 33 Common Interface Errors Cyclic Redundancy Runt Frame Errors Giant Frame Errors Check (CRC) Errors Frame's calculated checksum does not Frames are smaller Frames exceed the match the than the minimum maximum allowed transmitted frame size. size. checksum Indicative of noise, Caused by Results from interference, or misconfiguration or collisions or damaged equipment malfunctioning hardware. malfunctions network devices 34  Network Loop and Broadcast Storm Network Loops: Network Loops: Broadcast Broadcast Causes Solutions Storms: Causes Storms: Solutions Redundant Proper DHCP issues Monitor DHCP connections redundant Very large traffic End-device side connection broadcast Segment the configuration domains network Implement spanning tree protocol (STP) Educate users 35 Power Over Ethernet Issues Cabling Standard Power Budget Considerations Compatibility Management Must use Cat 5e or Devices must Switches have a better, recommend negotiate the limited power Cat 6A correct PoE mode budget (300–400W) Importance of (Alternative A, B, or Use "show power conductor thickness Four-pair) inline" command for (23 AWG > 24 AWG Challenges with monitoring for better devices only performance) supporting the first Shielded cabling PoE standard helps disperse heat efficiently 36 Activity: What Would You Do? The switch won’t power on. What troubleshooting steps would you take? 37 Summary NIC vs. Transceiver: NIC connects host to network (cable), transceiver adapts cable types Hub vs. Switch: Hub broadcasts to all devices, switch directs traffic to specific devices; bridge connects networks, keeps them logically unified STP: Prevents bridge loops and ensures network redundancy (Layer 2 protocol) 38