11-27-2017 06:29 PM - edited 03-05-2019 09:33 AM
Hello,
L2 2960X - Switch
L3 2921 - Router
This is the first time I've configured these using a L2 switch.
I have 2 remote sites that use very old applications that only use broadcasts. These remote sites need to be able to communicate thus the use for multicast helpers. I know for certain that Site A is configured correctly as it is working properly with other remote sites. Site B is the first site where I am forced to use a L2 switch rather than a L3 switch so I'm a little confused.
I'm using the 'Router on a stick' trunking method as SVI's are unsupported on this switch. All workstations are in VLAN100 and their default-gateway is the Gi0/1.100 sub-inteface on the router.
I need help to confirm if the config on this sub-interface is correct (or if it should even be on sub-int).
SITE B
Int Gig0/1.100
ip vrf-forwarding NameOfvrf
encapsulation dot1q 100
ip address 10.1.1.1 255.255.255.0
ip helper address x.x.x.x
ip directed-broadcast
ip pim sparse-mode
ip multicast helper-map broadcast 239.5.5.5 ACLname
ip multicast helper-map 239.5.5.5 10.1.1.255 ACLname
To test this, I connect a laptop to the switch and I receive an IP from DHCP. My laptop can ping other hosts in it's VRF from SITE A so connectivity is up. I open Ostinato (packet generator) on the laptop, assign the source IP as the laptops IP, and the destination as the broadcast address 10.1.1.255. I then jump back onto the router and when I do show ip mroute vrf *name* all I see is:
(*239.5.5.5), time/date, RP 10.*.*.*, flags SJCL
Incoming Int: Lspvif0, RPF nbr 10.*.*.*
Outgoing Int: Gi0/1.100 Forward/Sparse, date/time
I also used debug ip mpackets and I see nothing, so the broadcasts being generated by Ostinato are not being translated. I also tried changing the destination address to a laptop at SITE A but that's irrelivant as multicast packets are not leaving SITE B router.
Over at SITE A, when I use the show ip mroute vrf, I see that the incoming and outgoing interfaces are SVI's, not Lspvif0.
Thank you
Solved! Go to Solution.
11-27-2017 07:46 PM
Hi @dtcobra22
I think this like can be useful for you:
-If I helped you somehow, please, rate it as useful.-
11-27-2017 07:46 PM
Hi @dtcobra22
I think this like can be useful for you:
-If I helped you somehow, please, rate it as useful.-
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