I have attached a network that I recently created and in making the network i decided not to use vtp this time and on sw3 if I had a vlan only on that switch would I still have to add it to the other switches in order to create intervlans via the routers attached to the outside switches and then apply hsrp to each intervlan? for hsrp i need to put the same intervlans on both routers with different ips in the same subnet to make hsrp work with the intervlans correct? (so I would assign for example on RTR1 int gi0/1.12 with 192.168.7.2?)
In order to allow a VLAN that exists only on SW3 to reach the routers, you must include it in all the switches that exist between SW3 and the routers. Now if SW3 is the one in the middle (I can’t see the labels) then you must add the VLAN to the other two switches so that it can be trunked and eventually reach the routers for routing.
For HSRP to function you do have to use the same VLAN on both routers. As for the configuration of HSRP, you can see details in the HSRP lesson.
Hi Rene, Hi Laz,
I’ve to map some VLANs into other VLAN so that the “new VLANS” running on that switch have as default GW an IP configured on the “old VLANS”.
Hereby my configuration that doesn’t work. Can you please help me ?
Switch_default_GW:
vlan 599
name native
!
vlan 3301
name A
!
vlan 3302
name B
!
vlan 3303
name C
!
interface GigabitEthernet0/1
description link to Switch_for_remap T1/1/4
switchport trunk native vlan 599
switchport trunk allowed vlan 3301-3303
switchport mode trunk
!
interface Vlan3301
ip address 192.168.10.1 255.255.255.0
no ip route-cache
!
interface Vlan3302
ip address 192.168.20.1 255.255.255.0
no ip route-cache
!
interface Vlan3303
ip address 192.168.30.1 255.255.255.0
no ip route-cache
Switch_for_remap
vlan 599
name native
!
vlan 3301
name A_Original
!
vlan 3302
name B_Original
!
vlan 3303
name C_Original
!
vlan 3331
name A
!
vlan 3332
name B
!
vlan 3333
name C
!
interface TenGigabitEthernet1/1/4
description link to Switch_default_GW Gi0/1
switchport trunk native vlan 599
switchport trunk allowed vlan 3301-3303,3331
switchport mode trunk
switchport vlan mapping 3301 3331
switchport vlan mapping 3302 3332
switchport vlan mapping 3303 3333
switchport vlan mapping 3331 3301
switchport vlan mapping 3332 3302
switchport vlan mapping 3333 3303
l2protocol-tunnel stp
Mapping seems to work fine since I have a device on Switch_for_remap configured on VLAN 3331
interface GigabitEthernet1/0/1
switchport access vlan 3331
switchport mode access
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
3331 000c.4281.a733 DYNAMIC Gi1/0/1
Total Mac Addresses for this criterion: 1
And I see on the other switch (Switch_default_GW) the same mac address on the Original VLAN
sh mac address-table interface gigabitEthernet 0/1
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
3301 000c.4281.a733 DYNAMIC Gi0/1
Total Mac Addresses for this criterion: 1
But this device cannot reach his default GW even if i set a static IP address.
Thanks in advance for a feedback, wish you both a happy new year!
VLAN mapping allows you to translate VLAN IDs on one switch to a VLAN ID on another switch. That way, you can refer to the same VLAN with different VLAN IDs on different switches. This is helpful, particularly in a Metro Ethernet scenario, where the ISP is asked to send specific VLAN IDs across its infrastructure. If the customer VLAN ID numbers are already in use in the ISP’s infrastructure, then these are translated for transmission over the ISP, and are typically re-translated to their original values when they reach the remote customer site.
For clarity, let’s call your original VLAN IDs the Customer VLAN IDs (C-VLAN IDs), and the mapped VLAN IDs we’ll call Service Provider VLAN IDs (S-VLAN IDs).
Now in your case you are not “translating back” to the original C-VLAN IDs at the remote site, you are simply mapping one VLAN ID to another. I don’t have a definitive answer for you as to why you are unable to ping your gateway, but I do have the following comments that you can explore during your troubleshooting to resolve the issue:
On the trunk port of the Switch_for_remap switch, you must have both customer and service provider VLAN IDs allowed on the trunk. You should, therefore, also include 3332 and 3333 in your allowed list. (I know you’re testing only VLAN 3331 for the time being in your post, but this should be done for completeness.)
When mapping, you should only map your C-VLAN IDs to your S-VLAN IDs. You should not be mapping the opposite direction as well. So you must remove the last three mapping commands.
Other than that, at first glance, everything looks OK. Try these out and continue your troubleshooting. The following documentation may also be helpful for you:
Hi Laz,
thanks a lot for your feedback.
Since i needed a immediate solution, i’ve done a little workaround.
I’ve configured on the remap switch a port on the original VLAN and a port on the translated VLAN and patched them together, It works. Spanning tree doesn’t interfere 'cause it’s PVST.
I Will go on with troubleshooting based on your suggestions. I’ll let you know ASAP if It works.
BR
Aronne
Thanks for keeping us posted, and I’m glad you were able to find a workaround. Network engineers must often be inventive and innovative to resolve issues as they arise. Let us know how you get along!
