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LACP with STP Sim

March 12th, 2017 in Lab Sim, LabSim Go to comments

Question

You work for SWITCH.com. They have just added a new switch (SwitchB) to the existing network as shown in the topology diagram.

LACP_STP_topology.jpg

RouterA is currently configured correctly and is providing the routing function for devices on SwitchA and SwitchB. SwitchA is currently configured correctly, but will need to be modified to support the addition of SwitchB. SwitchB has a minimal configuration. You have been tasked with competing the needed configuring of SwitchA and SwitchB. SwitchA and SwitchB use Cisco as the enable password.

Configuration Requirements for SwitchA

– The VTP and STP configuration modes on SwitchA should not be modified.
– SwitchA needs to be the root switch for vlans 11, 12, 13, 21, 22 and 23. All other vlans should be left are their default values.

Configuration Requirements for SwitchB

– Vlan 21, Name: Marketing, will support two servers attached to fa0/9 and fa0/10
– Vlan 22, Name: Sales, will support two servers attached to fa0/13 and fa0/14
– Vlan 23, Name: Engineering, will support two servers attached to fa0/15 and fa0/16
– Access ports that connect to server should transition immediately to forwarding state upon detecting the connection of a device.
– SwitchB VTP mode needs to be the same as SwitchA.
– SwitchB must operate in the same spanning tree mode as SwitchA.
– No routing is to be configured on SwitchB.
– Only the SVI vlan 1 is to be configured and it is to use address 192.168.1.11/24.

Inter-switch Connectivity Configuration Requirements:

– For operational and security reasons trunking should be unconditional and Vlans 1, 21, 22 and 23 should tagged when traversing the trunk link.
– The two trunks between SwitchA and SwitchB need to be configured in a mode that allows for the maximum use of their bandwidth for all vlans. This mode should be done with a non-proprietary protocol, with SwitchA controlling activation.
– Propagation of unnecessary broadcasts should be limited using manual pruning on this trunk link.

Answer and Explanation:

We post the initial configuration of Sw-A & Sw-B here for your reference, you can try solving this sim by yourself before reading the asnwers below:

Initial Configuration (useless lines have been removed)

SwA:
hostname Sw-A
!
vtp mode transparent
!
spanning-tree mode rapid-pvst
!
vlan 98
!
vlan 99
 name TrunkNative
!
interface FastEthernet0/1
 switchport access vlan 98
 switchport mode access
!
interface FastEthernet0/3
 switchport access vlan 98
 switchport mode access
!
interface FastEthernet0/4
 switchport access vlan 98
 switchport mode access
!
interface Vlan1
 no ip address
 shutdown
!
end
Sw-B:
hostname Sw-B
!
vtp mode server
!
spanning-tree mode pvst
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface Vlan1
 no ip address
 shutdown
!
ip default-gateway 192.168.1.1
!
end

Solution

SW-A (close to router)
Note: If Sw-A does not have Vlan 11, 12, 13 we have to create them first with command “SW-A(config)#vlan 11,12,13”
SW-A(config)#spanning-tree vlan 11-13,21-23 root primary

SW-A(config)#vlan 21
SW-A(config-vlan)#name Marketing
SW-A(config-vlan)#exit

SW-A(config)#vlan 22
SW-A(config-vlan)#name Sales
SW-A(config-vlan)#exit

SW-A(config)#vlan 23
SW-A(config-vlan)#name Engineering
SW-A(config-vlan)#exit
SW-A(config)#interface range fa0/3 – 4
SW-A(config-if-range)#no switchport mode access
SW-A(config-if-range)#no switchport access vlan 98 (These two commands must be deleted to form a trunking link)
SW-A(config-if-range)#channel-group 1 mode active
SW-A(config-if-range)#channel-protocol lacp
SW-A(config-if-range)#no shutdown
SW-A(config-if)#interface port-channel 1
SW-A(config-if)#switchport mode trunk
SW-A(config-if)#switchport trunk native vlan 99 //this command will prevent the “Native VLAN mismatched” error on both switches
SW-A(config-if)#switchport trunk allowed vlan 1,21-23
SW-A(config-if)#no shut

Note: When you apply commands under “interface port-channel 1”, the same commands will be automatically applied to the physical member interfaces (of port-channel 1) so you don’t need to type them under physical member interfaces again.

——————————————————————————————–

SW-B (far from router)
SW-B(config)#vlan 21
SW-B(config-vlan)#name Marketing
SW-B(config-vlan)#exit

SW-B(config)#vlan 22
SW-B(config-vlan)#name Sales
SW-B(config-vlan)#exit

SW-B(config)#vlan 23
SW-B(config-vlan)#name Engineering
SW-B(config-vlan)#exit
SW-B(config)#vlan 99
SW-B(config-vlan)#name TrunkNative // not necessary to name it but just name it same as SwitchA
SW-B(config-vlan)#exit
SW-B(config)#interface range fa0/9 – 10
SW-B(config-if-range)#switchport mode access
SW-B(config-if-range)#switchport access vlan 21
SW-B(config-if-range)#spanning-tree portfast
SW-B(config-if-range)#no shutdown
SW-B(config-if-range)#exit

SW-B(config)#interface range fa0/13 – 14
SW-B(config-if-range)#switchport mode access
SW-B(config-if-range)#switchport access vlan 22
SW-B(config-if-range)#spanning-tree portfast
SW-B(config-if-range)#no shutdown
SW-B(config-if-range)#exit

SW-B(config)#interface range fa0/15 – 16
SW-B(config-if-range)#switchport mode access
SW-B(config-if-range)#switchport access vlan 23
SW-B(config-if-range)#spanning-tree portfast
SW-B(config-if-range)#no shutdown
SW-B(config-if-range)#exit

SW-B(config)#vtp mode transparent

SW-B(config)#spanning-tree mode rapid-pvst //Same as Sw-A

SW-B(config)#ip default-gateway 192.168.1.1 (you can get this IP from SW-A with command show cdp neighbour detail) // not sure about this command because the question says “No routing is to be configured on SwitchB”.

SW-B(config)#interface vlan 1
SW-B(config-if)#ip address 192.168.1.11 255.255.255.0
SW-B(config-if)#no shutdown
SW-B(config-if)#exit

SW-B(config)#interface range fa0/3 – 4
SW-B(config-if-range)#channel-group 1 mode passive //mode passive because “SwitchA controlling activation”
SW-B(config-if-range)#channel-protocol lacp
SW-B(config-if-range)#no shutdown

SW-B(config-if)#interface port-channel 1
SW-B(config-if)#switchport trunk encapsulation dot1q
SW-B(config-if)#switchport mode trunk
SW-B(config-if)#switchport trunk native vlan 99 //this command will prevent the “Native VLAN mismatched” error on both switches
SW-B(config-if)#switchport trunk allowed vlan 1,21-23
SW-B(config-if)#no shut

Note: For Sw-B we have to set the 802.1q trunking protocol (switchport trunk encapsulation dot1q) before converting it into a trunk because it is a 3500 series (or higher) switch which supports both ISL and 802.1Q and we have to explicitly set which trunking protocol to be used. Sw-A is a 2900x series (or lower) switch and does not support ISL trunking protocol (802.1Q is the only supported trunking protocol) so we can apply “switchport mode trunk” directly.

———————————————————

Some guidelines for configuring SwitchA & SwitchB:

Configuration Requirements for SwitchA

– The VTP and STP configuration modes on SwitchA should not be modified.
– SwitchA needs to be the root switch for vlans 11, 12, 13, 21, 22 and 23. All other vlans should be left are their default values
SW-A(config)#spanning-tree vlan 11-13,21-23 root primary

Configuration Requirements for SwitchB

– Vlan 21, Name: Marketing, will support two servers attached to fa0/9 and fa0/10
– Vlan 22, Name: Sales, will support two servers attached to fa0/13 and fa0/14
– Vlan 23, Name: Engineering, will support two servers attached to fa0/15 and fa0/16
– Access ports that connect to server should transition immediately to forwarding state upon detecting the connection of a device.
vlan …
name …
(VLANs must be created on both switches if not exist)
interface range fa0/x – y
switchport mode access
switchport access vlan
spanning-tree portfast
– SwitchB VTP mode needs to be the same as SwitchA. vtp mode transparent
– SwitchB must operate in the same spanning tree mode as SwitchA. spanning-tree mode rapid-pvst
– No routing is to be configured on SwitchB.
– Only the SVI vlan 1 is to be configured and it is to use address 192.168.1.11/24.
interface vlan 1
ip address 192.168.1.11 255.255.255.0

Inter-switch Connectivity Configuration Requirements:

– For operational and security reasons trunking should be unconditional and Vlans 1, 21, 22 and 23 should tagged when traversing the trunk link.
– The two trunks between SwitchA and SwitchB need to be configured in a mode that allows for the maximum use of their bandwidth for all Vlans. This mode should be done with a non-proprietary protocol, with SwitchA controlling activation.
SW-A(config)#interface range fa0/3 – 4
SW-A(config-if)#no switchport mode access
SW-A(config-if)#no switchport access vlan 98
Note: Two above commands must be deleted first to form a trunking link.

Although the first requirement asks us to configure trunking but we can ignore this task because we only need to configure trunking under their Port-channel (in the next task)

– The two trunks between SwitchA and SwitchB need to be configured in a mode that allows for the maximum use of their bandwidth for all Vlans:
SW-A(config)#interface range fa0/3 – 4
SW-A(config-if)#channel-group 1 mode active
SW-A(config-if)#channel-protocol lacp
SW-A(config-if)#no shutdown
– Trunking should be unconditional and Vlans 1, 21, 22 and 23 should tagged when traversing the trunk link:
SW-A(config-if)#interface port-channel 1
SW-A(config-if)#switchport mode trunk
SW-A(config-if)#switchport trunk native vlan 99 //this command will prevent the “Native VLAN mismatched” error on both switches
SW-A(config-if)#no shut
—————————————
SW-B(config)#interface range fa0/3 – 4
SW-B(config-if)#channel-group 1 mode passive
SW-B(config-if)#channel-protocol lacp
SW-B(config-if)#no shutdown
SW-B(config-if)#interface port-channel 1
SW-B(config-if)#switchport trunk encapsulation dot1q
SW-B(config-if)#switchport mode trunk
SW-B(config-if)#switchport trunk native vlan 99 //this command will prevent the “Native VLAN mismatched” error on both switches
SW-B(config-if)#no shut

– Propagation of unnecessary broadcasts should be limited using manual pruning on this trunk link. SW-A(config)#interface port-channel 1
SW-A(config-if)#switchport trunk allowed vlan 1,21-23
—————————————
SW-B(config)#interface port-channel 1
SW-B(config-if)#switchport trunk allowed vlan 1,21-23
Note: When configure this command under Port-channel 1, the same command will be applied to physical member interfaces (of port-channel 1) so you don’t need to type them under physical member interfaces again.

Some notes for this sim:
+ You should check the initial status of both switches with these commands: show vtp status (transparent mode on switchA and we have to set the same mode on switchB), show spanning-tree [summary] (rapid-pvst mode on switchA and we have to set the same mode on switchB), show vlan (check the native vlan and the existence of vlan99), show etherchannel 1 port-channel and show ip int brief(check if Port-channel 1 has been created and make sure it is up), show run (to check everything again).
+ When using “int range f0/x – y” command hit space bar before and after “-” otherwise the simulator does not accept it.
+ You must create vlan 99 for the switchB. SwitchA already have vlan 99 configured.
+ At the end, you can try to ping from SwitchB to RouterA (you can get the IP on RouterA via the show cdp neighbors detail on SwitchA), not sure if it can ping or not. If not, you can use the “ip default-gateway 192.168.1.1” on SwitchB.
+ The name of SwitchA and SwitchB can be swapped or changed so be careful to put your configuration into appropriate switch.

We hope with this information our candidates can find the best solution in the exam. If you learn anything new about this sim please share with us!

Other lab-sims in this site:

MLS and EIGRP Sim
VTP Lab 2
VTP Lab
Spanning Tree Lab Sim
AAAdot1x Lab Sim

Comments
Comment pages
1 56 57 58 52
  1. mills
    November 20th, 2017

    finally, the link above wont be there for ever. i do not intend to hurt the feelings of certprepare.

  2. Shayan
    November 21st, 2017

    SW-A(config-if-range)#no switchport access vlan 98

    I am have a problem,When i type (no switchport mode access) it rejects the command

    SW-A(config)#interface range fa0/3 – 4
    SW-A(config-if-range)#no switchport mode access

    Command rejected: An interface must be configured to the Access or Trunk modes to be configured to NoNegotiate.

    PLEASE HELP

  3. Aimee
    November 21st, 2017

    With the Blessing of Allah SWT, today i have passed my CCNP switch exam , this is really an excellent website for everyone to prepare for cisco certifications.
    And one very important thing…..guys all questions of premium dumps are valid but not all of their answers are correct…..so if u have any doubt please clarify on cisco website tutorial .

  4. Jasim
    November 22nd, 2017

    @ Aimee…Congrats!
    so the switch portion here in this website is good enough? I’m taking it soon

  5. Netmenator
    November 23rd, 2017

    why we added switchport trunk encapsulation dot1q on the trunk from Switch B side and not from Switch A side ???

  6. Mrki
    November 25th, 2017

    @ Netmenator
    switchport trunk encapsulation dot1q command is needed on older switches

  7. Netmenator
    November 25th, 2017

    how do you know in the exam we should / shouldn’t use port channel ??

  8. Mrki
    November 25th, 2017

    The two trunks between SwitchA and SwitchB need to be configured in a mode that allows for the maximum use of their bandwidth for all vlans. This mode should be done with a non-proprietary protocol, with SwitchA controlling activation.

  9. Morcowbel293
    November 26th, 2017

    This says to use “spanning-tree vlan 11-13,21-23 root primary”. However that only works during this ‘session’ I guess, by lowering the priority to a value low enough to make it the root. Would it be better, or incorrect to hardset “spanning-tree vlan 11-13,21-23 priority 0”, so that it would be impossible for another switch to have a lower priority? Anyone have any insight into if my thought would be good or bad on the test?

  10. Morcowbel293
    November 27th, 2017

    Taking test today. Anyone have thoughts on the above comment?

  11. melo.man
    November 29th, 2017

    can someone please send me the latest dump(s) for the ccnp switch test. i would really appreciate it.

    {email not allowed}

    thank you so much
    meloman

  12. melo.man
    November 29th, 2017

    please send to 9meloman @ gmail com

  13. addie
    November 29th, 2017

    i don’t know why i have to put “ip-default gateway 192.168.1.1” on switch?
    any explanation?

  14. addie
    November 29th, 2017

    @ ip-helper

    this lab doesn’t support this command or any other problem?
    “SW-B(config-if)#interface port-channel 1
    SW-B(config-if)#switchport trunk encapsulation dot1q
    SW-B(config-if)#switchport mode trunk”
    or even if they can’t be applied in this PT switches but i have to apply them on real exam?

    please reply soon

  15. iphelper
    November 29th, 2017

    @addie, the “switchport trunk encapsulation dot1q” can be done only on 3500 multilayer switches. The LACP lab packet tracer lab provided here uses 2690 model switches for both Switch A and Switch B instead.

    Use my packet tracer version of LACP lab instead:
    https://www.dropbox.com/s/n5frxw9z13jsfc6/300-115_LACP-Lab%20PT%202017.zip?dl=0

  16. addie
    November 29th, 2017

    why i have to put “ip-default gateway 192.168.1.1” on switch?
    any explanation?
    @iphelper

  17. addie
    November 29th, 2017

    and 1 more important thing,
    i’m gonna sit for this ccnp switch exaam for recertifying my existing ccnp switch certificate.so is it gonna work or any suggestion you might wanna give?

    thanks in advance

  18. Nick
    November 29th, 2017

    DO NOT USE http://www.myexamcollection.com/ ITS A FAKE

  19. Anonymous
    November 29th, 2017

    how will management traffic pass through trunk link when it is not included in allowed list?

  20. chowchow
    December 1st, 2017

    Could I know all of these better to practice on which packet tracer version? Any other simulator that I can use? I’m taking my exam in another weeks time. thanks

  21. Anonymus
    December 7th, 2017

    Hy guys, the information provided by the site is valid.
    Don’t forget about the “switchport trunk encapsulation dot1q”, I completely forgot about it and lost a lot of time with the sim and in the end I failed because I panicked I thought I did not have time to finish (in reality I had the time…).

    If you don’t apply the command on the second switch you will not be able to configure the port in trunk and receive the following error “An interface whose trunk encapsulation is Auto can not be configured to trunk mode”. Somehow the trunk and lacp worked, even with interface fa0/3 and 0/4 configred liked this:

    SW-B(config)#interface range fa0/3 – 4
    SW-B(config-if)#switchport trunk native vlan 99
    SW-B(config-if)#switchport trunk allowed vlan 1,21-23
    SW-B(config-if)#switchport mode access
    SW-B(config-if-range)#channel-group 1 mode passive
    SW-B(config-if-range)#channel-protocol lacp
    SW-B(config-if-range)#no shutdown

    SW-B(config-if)#interface port-channel 1
    SW-B(config-if)#switchport trunk native vlan 99
    SW-B(config-if)#switchport trunk allowed vlan 1,21-23
    SW-B(config-if)#switchport mode trunk
    SW-B(config-if)#no shut

    Good luck!

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