I setup a VLAN on one subnet now I cant ping to other subnets?

[leanok1]

Here's a photo of the topology. I created a vlan on Switch A and trunked it to Router A with a 1941 router. Seems I can't ping to any other device in the other subnets. Is this normal or did I do something wrong? 

[David Ruess]

Hello,

Not bad but you missed a couple of minor things. First lets start with RIP. It is a Classful protocol by default so without any other commands it will lump subnets into their classfull address and mask. So if you subnet a class A address then it will just be advertised as 1 class A address and mess up routing. TO fix that issue the following command on all routers.

conf t

router rip

no auto-summary

Then you have the PC 0 in the wrong VLAN. 

interface GigabitEthernet0/0

ip address 170.66.0.66 255.255.0.0

duplex auto

speed auto

!

interface GigabitEthernet0/0.10

encapsulation dot1Q 10

ip address 66.1.1.1 255.0.0.0

You have the 0/0.10 interface configured with a dot1q tag of 10 so it knows to accept frames from VLAN 10. The G0/1 interface however does not have any dot1q tag. Which means use the native VLAN (an untagged VLAN on a trunk link). By default on CISCO that's VLAN 1. You had the PC in VLAN 10 with the printer. Once I moved it to VLAN 1 and fixed the routing as mentioned above everything worked.

Hope that helps

-David

[leanok1]

Thanks for the explanation! I really appreciate it. The goal is for PC 0 to ping PC 3, PC 1, and Server 0. I followed the steps above and still cant seem to ping PC 0 to the other PCs and server. 

[paul driver]

Hello
The reason you do not have connectivity it two fold.

• You are running RIP version 1 which by default is classful, to allow classless subnets to be advertised correctly you would need to enable RIP version 2
  
  
•  You have overlapping ip addressing on each router, as such each router WILL prefer its own subnet over any advertised by RIP, changing that addressing will provide connectivity.
  
  

Lastly you mention you wish to provide intervlan routing, and not ROAS however you cannot allow vlan extension with the current topology you have setup.

[Martin L · Accepted solution]

IP address 170.66.0.66 255.255.0.0 should be on GigabitEthernet0/0.10, not 66.1.1.1 which I not sure why or where is goes. So either move 170 IP to 0/0.10 and remove 66.1.1.1  or remove GigabitEthernet0/0.10 completely.  If you planing on using ROAS, then keep GigabitEthernet0/0.10 and encapsulation dot1Q.  I do not see reason for it right now.

interface GigabitEthernet0/0

no ip address

!

interface GigabitEthernet0/0.10

encapsulation dot1Q 10

ip address 170.66.0.66 255.255.0.0

!

router rip

no auto

Regards, ML
**Please Rate All Helpful Responses **

[leanok1]

so I moved 170 IP to 0/0.10
What's the IP now for 0/0?

I'm not too sure but I think the goal for this Lab is Intervlan routing with ROAS? 

[balaji.bandi]

What's the IP now for 0/0?

there is no IP to configure on that interface since you looking to configure 802.1q tagging with sub interfaces.

example and good explanation :

https://www.firewall.cx/cisco-technical-knowledgebase/cisco-routers/336-cisco-router-8021q-router-stick.html

[leanok1]

Thank you! How am I now able to ping from PC0 to PC 3, PC 2, and Server 0? Because I still can't do that. I can now ping from PC 0 to the router after revising

[David Ruess]

Not sure if you read my solution above but what I listed fixed your issues. I downloaded your packet tracer and I was able to ping everything.

-David

[Martin L]

no IP for GigabitEthernet0/0,  if you add another vlan, like vlan 20, on switch A, then Router A2 would need another sub-interface to route between those vlans. i.e

interface GigabitEthernet0/0.20

encapsulation dot1Q 20

ip address x.y.z

all routers should have

no auto-summary

under Rip

see attach file

Regards, ML
**Please Rate All Helpful Responses **

[MHM Cisco World]

sure you can not ping because the when I do

show ip route

there is no "L" for RouterB and RouterC !!!

solution, make RouterB and RouterC same model of RouterA,
this may be bug in PKT so change the router to one model RouterA (since RouterA have no issue with "L" route).

[leanok1]

Sorry for the late reply, but it works now. Thank you so much to everyone!