CCIE TOPICS

 

what is a errdisable recovery in Switch Administrator.

Errdisable recovery is a feature on network switches that automatically re-enables ports that have been disabled due to errors, like link flaps or security violations. It helps to minimize downtime by fixing issues that caused the ports to be disabled.

what is a MENNAGING MAC-ADDRESS TABLE in Switch Administrator.

A managing MAC address table in a switch keeps track of which MAC addresses are connected to which ports. It helps the switch send data to the correct device on the network.

what is a L2 MTU in Switch Administrator.

Sure! The L2 MTU is the biggest size of a data packet that a switch can handle at once. If a packet is bigger than this size, the switch will split it into smaller pieces

what is a CDP AND LLDP in LAYER 2 PROTOCOL 

CDP (Cisco Discovery Protocol) and LLDP (Link Layer Discovery Protocol) are Layer 2 protocols used for discovering and sharing information about neighboring network devices. CDP is Cisco-specific, while LLDP is a standard used by many vendors.

what is a UDLD in LAYER 2 PROTOCOL 

UDLD is a tool that checks if both ends of a network cable are working together. If one end isn’t sending or receiving data properly, UDLD can spot the problem and help fix it.

what is a normal and extend VLAN and voice VLAN in troubleshoot VLAN

Normal VLAN: Standard VLAN used for regular network traffic.

Extended VLAN: VLANs numbered 1006-4095, used for larger networks.

Voice VLAN: Dedicated VLAN for voice traffic to ensure quality for VoIP calls.


what is a difference between VTPv1 and v2 and v3 nad VTP Pruning

VTPv1: Basic VLAN Trunking Protocol, supports VLANs 1-1005.

VTPv2: Enhances VTPv1, adds support for VLANs 1006-4095 and improved advertisement.

VTPv3: Further improves with support for extended VLANs, enhanced security, and better scalability.

VTP Pruning: Reduces unnecessary VLAN traffic on trunk links by only forwarding VLAN traffic that is needed on a specific link.

what is a dot1Q in trunking. 

802.1Q (Dot1Q) is a Layer 2 protocol used for VLAN tagging in trunking. It adds a tag to Ethernet frames to identify which VLAN the frame belongs to, allowing multiple VLANs to traverse a single network link.

what is a Native VLAN in trunking.

The Native VLAN in trunking is the VLAN that carries untagged traffic on a trunk link. It is the default VLAN for any frames that don't have VLAN tags.

what is a Manuall pruning in trunking.

Manual pruning in trunking involves manually configuring which VLANs are allowed to pass through a trunk link, reducing unnecessary traffic and improving network efficiency.

what is this in Troubleshoot and implement in etherchannel write again in short LACP, PAgP, manual layer 2, layer 3 load-balancing etherchannel misconfiguration guard

LACP, PAgP, Manual: Protocols for creating EtherChannels.

• LACP (Link Aggregation Control Protocol): Layer 2, standard-based.
• PAgP (Port Aggregation Protocol): Layer 2, Cisco proprietary.
• Manual: Layer 2, manually configured.

Load-Balancing: Distributes traffic across multiple links in an EtherChannel.

EtherChannel Misconfiguration Guard: Prevents network issues by detecting and preventing incorrect EtherChannel configurations.


implement and troubleshoot spanning-tree 1.1.f (i) PVST+/RPVST+/MST 1.1.f (ii) switch priority, port priority, path cost, STP timers 1.1.f (iii) port fast, BPDUguard,

1.1.f (i) PVST+/RPVST+/MST:

• PVST+: Makes a separate network path for each VLAN to avoid loops.
• RPVST+: A faster version of PVST+ that quickly adapts to changes.
• MST: Groups several VLANs together to reduce the number of paths needed.

1.1.f (ii) Switch Priority, Port Priority, Path Cost, STP Timers:

• Switch Priority: Decides which switch gets to be the main one.
• Port Priority: Affects which ports are used for sending data.
• Path Cost: Shows how "costly" a path is to reach the main switch.
• STP Timers: Control how long STP waits before making changes (Hello Timer, Forward Delay Timer, Max Age Timer).

1.1.f (iii) PortFast, BPDU Guard:

• PortFast: Lets ports start working right away, skipping some checks.

BPDU Guard: Turns off ports that get unexpected STP signals to prevent problems.


what is a RPF

RPF stands for Reverse Path Forwarding. It's a security mechanism used in networking to prevent loops and ensure that data packets are sent in the correct direction.

Compare routing protocol types distance vector link state path vector.

1. Link State: Routers send out updates about their connections to every router in the network, so everyone has a complete view of the network and can find the best route. It’s like everyone working off the same network map.

2. Path Vector: Routers track the entire route to each network and use this information to make routing decisions. It’s like keeping a detailed log of all the routes taken to reach different destinations.
   
   Distance Vector: Routers tell their neighbors which routes they know about, and those neighbors do the same. It’s like passing around a list of directions to everyone. 

OSPF (v2 and v3) 2.6.a Describe packet types 2.6.a (i) LSA types (1, 2, 3, 4, 5, 7, 9) 2.6.a (ii) Route types (N1, N2, E1, E2) 2.6.b Implement and troubleshoot neighbor relationship 2.6.c Implement and troubleshoot OSPFv3 address-family support 2.6.c (i) IPv4 address-family 2.6.c (ii) IPv6 address-family 2.6.d Implement and troubleshoot network types, area types and router types 2.6.d (i) Point-to-point, multipoint, broadcast, non-broadcast 2.6.d (ii) LSA types, area type: backbone, normal, transit, stub, NSSA, totally stub 2.6.d (iii) Internal router, ABR, ASBR 2.6.d (iv) Virtual link

Packet Types

1. Hello: Used to discover and maintain neighbor relationships.
2. Database Description: Describes the OSPF database contents.
3. Link State Request: Requests detailed information about specific LSAs.
4. Link State Update: Sends LSAs with routing information.
5. Link State Acknowledgment: Confirms receipt of LSAs.

LSA Types

1. Type 1: Router LSA - Shows information about routers and their interfaces.
2. Type 2: Network LSA - Describes networks and the routers connected to them.
3. Type 3: Summary LSA - Provides information about networks from other areas.
4. Type 4: ASBR Summary LSA - Shows routes to ASBRs (Autonomous System Boundary Routers).
5. Type 5: External LSA - Describes routes to external networks.
6. Type 7: NSSA External LSA - Similar to Type 5 but for NSSA (Not So Stubby Areas).
7. Type 9: Opaque LSA - Used for additional information beyond standard LSAs.

Route Types

1. N1 (Intra-area route): Route within the same area.
2. N2 (Inter-area route): Route between different areas.
3. E1 (External route with internal cost): External route with internal OSPF cost.
4. E2 (External route with external cost): External route with only external cost.

Implementing and Troubleshooting

1. Neighbor Relationships: Ensure routers can see each other and establish connections.

2. OSPFv3 Address-Family Support: Configure and troubleshoot OSPF for both IPv4 and IPv6.

   • IPv4: Traditional OSPF setup.
   • IPv6: OSPFv3 for IPv6 addresses.

Network Types, Area Types, and Router Types

1. Network Types:

   • Point-to-Point: Direct connection between two routers.
   • Multipoint: Multiple routers on the same network.
   • Broadcast: Multiple routers on a network that supports broadcasting (e.g., Ethernet).
   • Non-Broadcast: Similar to broadcast but without automatic neighbor discovery (e.g., Frame Relay).

2. Area Types:

   • Backbone Area: Core area (Area 0).
   • Normal Area: Regular area with full OSPF features.
   • Transit Area: Area between different OSPF areas.
   • Stub Area: Simplified area with default routes to other areas.
   • NSSA (Not So Stubby Area): Similar to a stub area but can accept external routes.
   • Totally Stubby Area: Even more restricted than a stub area, only default routes.

3. Router Types:

   • Internal Router: A router within a single area.
   • ABR (Area Border Router): Connects multiple OSPF areas.
   • ASBR (Autonomous System Boundary Router): Connects OSPF to other routing protocols.

Virtual Link: A logical connection between two OSPF routers across a non-backbone area to maintain area connectivity.


3.1.a Implement and troubleshoot MPLS operations 3.1.a (i) Label stack, LSR, LSP 3.1.a (ii) LDP 3.1.a (iii) MPLS ping, MPLS traceroute 3.1.b Implement and troubleshoot basic MPLS L3VPN 3.1.b (i) L3VPN, CE, PE, P 3.1.b (ii) Extranet (route leaking) 3.1.c Implement and troubleshoot encapsulation 3.1.c (i) GRE 3.1.c (ii) Dynamic GRE 3.1.d Implement and troubleshoot DMVPN (single hub) 3.1.d (i) NHRP 3.1.d (ii) DMVPN with IPsec using preshared key 3.1.d (iii) QoS profile 3.1.d (iv) Pre-classify

MPLS and VPNs

3.1.a MPLS Operations

• Label stack: A sequence of labels assigned to a packet as it travels through the MPLS network.

• LSR (Label Switching Router):

• An LSR (Label Switching Router) is a special type of router used in MPLS (Multiprotocol Label Switching) networks. Instead of routing based on IP addresses, it looks at labels attached to data packets.

• LSP (Label Switched Path): A pre-established path between two LSRs that uses labels to forward packets.

• LDP (Label Distribution Protocol): A protocol used to distribute labels between LSRs.

• MPLS ping and MPLS traceroute: Tools used to troubleshoot MPLS networks.
  
  

  Imagine a package being delivered.

  Label Stack: The stickers on the package.

  LSR: The postman who reads the stickers.

  LSP: The planned route for the postman.

  LDP: The system that teaches the postman about the stickers.

  MPLS ping and MPLS traceroute: Tools to check if the postman is delivering packages correctly.

3.1.b Basic MPLS L3VPN

• L3VPN: A virtual private network (VPN) that operates at Layer 3 of the OSI model.

• CE: Customer Edge router, connects the customer's network to the provider's network.

• PE: Provider Edge router, connects the provider's network to the customer's network.

• P: Provider router, located within the provider's network.

• Extranet (route leaking): A type of L3VPN where routes are leaked between different provider networks.

3.1.c Encapsulation

• GRE (Generic Routing Encapsulation): A tunneling protocol used to encapsulate IP packets within another IP packet.
• Dynamic GRE: A version of GRE that can dynamically establish tunnels based on traffic patterns.

3.1.d DMVPN (Single Hub)

• DMVPN: Dynamic Multipoint VPN, a scalable VPN solution for connecting multiple remote sites to a central hub.
• NHRP (Next Hop Resolution Protocol): A protocol used to resolve the next-hop address for tunnel endpoints.
• DMVPN with IPsec using preshared key: DMVPN can be combined with IPsec for encryption using a pre-shared key.
• QoS profile: A set of parameters used to control the quality of service for traffic.

Pre-classify: Classifying traffic into different priority levels before applying QoS policies.