Multicast routing

[fspinelli2000]

Hi all,

I am trying to route some multicast packets, but I'm having some problems with TTL.

I have tried to route...

I can't change source TTL for multicast packets, so some multicasts are arriving on the router with TTL=1. As we know, a router decreases TTL and discards this packet.

So, my question is: Can I change TTL of a multicast packet on a Cisco router? Or can it pass through without changing its value?

[jarar_m01 · Accepted solution]

In order to solve the issue, you need to increase the TTL. This is done at the application level on the Sender. For more information, refer to your multicast application instruction manual.

[fspinelli2000]

My problem is that I can't change it on the Application level, the network which I am configuring just have to pass the multicast the way it is. But thanks for the answer.

Probable I'll have to change TTL using a IPtables firewall.

[jarar_m01]

Can you try adding a static Mroute on that router

ip mroute <source_Address> 255.255.255.255 <Dest>

Also try to reset the ttl value if this does not work

please follow this link, it might help you.

http://www.cisco.com/c/en/us/td/docs/ios/12_2/ipmulti/command/reference/fiprmc_r/1rfmult2.html 

BR,

Jarar

[fspinelli2000]

Thanks for the help. But nothing work here to change TTL on the router, so I will ask to the client to increase the TTL or install a IPTables to change it.