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inter-vlan with VLSM and Router on a stick not working

Zach8585
Level 1
Level 1

Studying for my CCNA, including a cisco lab with one switch and one router.  Right now it's not attached to the internet (via cable modem), that will be later down the road.

 

Here's a brief overview of my current set up:

 

on the switch (3560 8 ports):

three vlans:

1 - native; 192.168.1.253 255.255.255.252

20 - 192.168.1.66 255.255.255.240

30 - 192.168.1.2 255.255.255.192

Gi0/1 set for dot1q trunking to router's Gi0/0 interface

 

on the router (2800 series):

Gi0/0 - 192.168.1.254 255.255.255.252

Gi0/0.20 - 192.168.1.65 255.255.255.240

Gi0/0.30 - 192.168.1.1 255.255.255.192

 

DHCP is set up on router as following:

 

VLAN20 scope

- Network 192.168.1.64 255.255.255.240

- Default-router 192.168.1.65

 

VLAN30 scope

- Network 192.168.1.0 255.255.255.192

- default-router 192.168.1.1

 

On the switch, I have FA0/1 and FA0/2 set to VLAN 20, and FA0/3 set to VLAN 30.

 

When I have two separate computers plugged into FA0/1 and FA0/2, they can see each other no problem, ping, file share, etc.

 

However, when I put one of the two computers onto FA0/3, they can't see each other, and I've verified that DHCP is working correctly on both VLANS.  Yet, they can ping the switch's VLAN interface and router-sub interfaces of both VLANS.  In other words, they are crossing over the VLAN/Subnet "borders".  So I don't get what is the problem when inter-vlan routing is obviously happening at layer 3 (Router) when I'm able to ping the switch's interface and router's subinterface across the vlan and subnets.

 

Anyone have any idea what I'm missing?  Show IP Route does show the networks via the correct sub-interface.  both switch and router can ping all six interface ip addresses, both computers can ping all six.

 

Any help would be appreciated, especially since I'm planning to take my CCNA test by the end of July.

 

Thanks

1 Accepted Solution

Accepted Solutions

chrihussey
VIP Alumni
VIP Alumni

Can the PCs ping each other across VLANs?

Can you post the configs?

Thanks

View solution in original post

2 Replies 2

chrihussey
VIP Alumni
VIP Alumni

Can the PCs ping each other across VLANs?

Can you post the configs?

Thanks

I had solved the issue.  It was actually a network interface card issue on my server.  After resolving that issue, I was able to ping across the VLAN "border".

 

Thanks

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