06-16-2017 08:57 AM - edited 03-05-2019 08:43 AM
So guys I'm at a loss here. We have a LAN in which we need to simulate user devices being able to send IGMP multicast traffic between networks. In this lab there is an old 3750 48 port switch and a 3800 router.
Don't scream it was this way before I started but the switch is essentially blank. All devices plugged into it are assigned to vlan 1 as access ports and the customer says this setup is working. So I powered up the router blank at this point also and connected f1/0/48 on the switch into G0/1 on the router.
No connection which is to be expected at this point. I logged into the router and no shut port G0/1 which brought it up. I then configured f1/0/48 on the switch as a trunk port with the following commands (switchport trunk encapsulation dot1q, switchport mode trunk). I then gave the switch a management vlan of 200 with an address of 10.0.0.10. Finally on the switch I set the default-gateway to 10.0.0.30.
Back on the router I made a sub interface g0/1.200 and set encapsulation to dot1q. Finally, the last two things I did were to enable multicast with ip multicast-routing and made a default route to the switch 0.0.0.0 0.0.0.0 g0/1.
Right the two devices can see each other via show CDP neighbors but they cannot ping each other or telnet to each other.
Solved! Go to Solution.
06-16-2017 09:22 AM
Making the native VLAN of the trunk the same as the management VLAN will probably fix the issue.
Add the following to the g0/1.200 interface:
encapsulation dot1Q 200 native
Add the following to the 3750 trunk port:
switchport trunk native vlan 200
Hope this helps
06-16-2017 09:22 AM
Making the native VLAN of the trunk the same as the management VLAN will probably fix the issue.
Add the following to the g0/1.200 interface:
encapsulation dot1Q 200 native
Add the following to the 3750 trunk port:
switchport trunk native vlan 200
Hope this helps
06-16-2017 10:40 AM
Omg lol, I'm so mad at myself. You are right, the native vlan was incorrect.
06-16-2017 09:24 AM
The default route should use the IP as the next hop but that is not really the problem.
Not sure what multicast has to do with it either.
Can you post the configurations of both devices and also a "sh vlan" from the switch.
Jon
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide