Core Switch

[cheysser_03]

Dears

This is my first time to configure core switch on packet tracer and still confusing in core switch how to interconnect all the core switch? and I can't put any IP ADDRESS for each port

Regards

[Dennis Mink]

what type of switch is it?  not all are full layer 3 capable.

try a trunk and an svi interface

[cheysser_03]

Hi Dennis,

I tried that trunk but it's giving me an error" 

Command rejected: An interface whose trunk encapsulation is "Auto" can not be configured to "trunk" mode.

model: 3560

[Seb Rupik · Accepted solution]

Hi there,

Add the following config to your trunk port:

!
int gix/x
  switchport trunk encap dot1x
  swithport mode trunk
!

[cheysser_03]

Hi Dennis,

Still same problem what am achieving for this diagram to have a redundant connection if 1 connection goes down still they can ping each other
Regards

[shaps · Accepted solution]

The diagram only shows one connection from the edge switch to the core switch, so when one switch goes down you are always going to isolate at least one switch.
If you add anoterh link between the edge switch and the core then try and add in the commands above on each of the core switches as suggested before.

[Seb Rupik]

I suggest you create SVIs on the core switches, establish port-channels between the core switches and create a Layer3 mesh between them advertising routes via IGP.

Looking at SW_01 you could have:

!
vlan 12
vlan 13
vlan 14
!
int vlan 12
  desc LINK_TO_SW_02
  ip address 10.0.12.1 255.255.255.252
!
int vlan 13
  desc LINK_TO_SW_03
  ip address 10.0.13.1 255.255.255.252
!
int vlan 14
  desc LINK_TO_SW_02
  ip address 10.0.14.1 255.255.255.252
!
int po1
  desc LINK_TO_SW_02
  switchport trunk encap dot1q
  switchport trunk allowed vlan 12
  switchport mode trunk
!
int po2
  desc LINK_TO_SW_03
  switchport trunk encap dot1q
  switchport trunk allowed vlan 13
  switchport mode trun
!
int po3
  desc LINK_TO_SW_04
  switchport trunk encap dot1q
  switchport trunk allowed vlan 14
  switchport mode trunk
!
int range gi1/0/1-2
  desc LINK_TO_SW_02
  channel-group 1 mode active 
!
int range gi1/0/3-4
  desc LINK_TO_SW_03
  channel-group 2 mode active
!
int range gi1/0/5-6
  desc LINK_TO_SW_04
  channel-group 3 mode active
!
router ospf 1
  router-id 1.1.1.1
  nassive-interface default
  no passive-interface vlan 12
  no passive-interface vlan 13
  no passive-interface vlan 14
  ! 
  network 10.0.12.0 0.0.0.255 area 0
  network 10.0.13.0 0.0.0.255 area 0
  network 10.0.14.0 0.0.0.255 area 0
!

You will need the above config to suit your ore switches (ie the switchport naming scheme) and to set up the other routers in similar manner to receive the port-channel links and the terminate the point-to-point links.

Cheers,

Seb.