CCNP Exam Prep Tips and Must Knows

StudyStudentAnnouncementThings You Need to Know about Routing between VLANs

InterVLAN  routing using an external router

  • Provide a single trunk link from switch to router
  • Router physical interface is divided into logical subinterfaces
  • Each router of interface acts as a gateway for one VLAN
  • InterVLAN in routing using a switched virtual interface (SVI)
  • Multilayer switches use SVIs for routing between VLANs new line

SVI configuration

  • switch (config) #ip routing
  • switch (config) # interface vlan10
  • switch (config-if) # ip address 10. 1.10.1 255.255.255.0
  • switch (config-if) # no shutdown
  • switch (config) # interface vlan20
  • switch (config-if) # ip address 10.1.20.1 255.255.255.0
  • switch (config-if) # no shutdown

Routed ports on a multilayer switch

  • Physical switch port with Layer 3 capability
  • Not associated with any VLAN
  • Requires removal of Layer 2 port functionality
  • Configured like a router interface but does not support VLAN subinterfaces
  • Used when a switch has one port per VLAN or subnet only
  • Useful for point-to-point Layer 3 switch links

Configuration of the routed interface

  • switch (config) # ip routing
  • switch (config) # interface fastethernet 0/24
  • switch (config-if) # no switchport
  • switch (config-if) # ip address 10.1.10.1 255.255.255.0

Routing protocol configuration

  • switch (config) # ip routing
  • switch (config) # router EIGRP 100
  • switch (config-router) #no auto-summary
  • switch (config-router) #passive-interface default
  • switch (config-router) #no passive-interface fa0/24
  • switch (config) # interface fa0/24
  • switch (config-if) #description uplink
  • switch (config-if) #IP summary-address eigrp 100 10.1.0.0 255.255.244.0

Make sure you can configure:

  • A routed port
  • A routing protocol
  • An SVI

Make sure you are familiar with:

  • Show ip route
  • Show ip interface brief
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