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IPTV multicast dropping packets

IPTV multicast dropping packets

New Contributor III
Hi guys,I have been working with IPTV for one year, so, all switch involved in this topology are x460, in this network I have mpls and vr created, nonetheless the multicast traffic is going through a specific VR with pim enabled.Everything is working properly, where on the main switch I have 2x460 in stack and two 10g ports going to other switch and 6 gigabit port going to another x460, in both case I have LACP enabled.
So, the curious situation that sometimes I can see some channels get a little bit checkered for some seconds, once it means that some dropped packed happened, but it just happens over traffic that is going through gigabit ports.In order for trying to solve this issue, we changed the SFP, optical patch cords, added more giga ports, increase the buffer ports to 100%, and with these stuff we could improve the transmission but not eliminated it in definitive.what we could notice that, sometime is still being logged some drop packets in these gigabit interfaces, where is causing this bad experience.I have tried to do a lot of thing to finished this dropped packets off. I could decrease the number of this incidents but not eliminated.I've been thinking that it could be the cpu process when using a gigaport where these are shared with the main cpu, different of 10g modules where they have a specific module to process all over the traffic.
Would someone get the same experience using x460 (not G2)? how would you solve this issue?

New Contributor
Segment your network into smaller boundaries or get larger interfaces. Issue is that more than one gig of traffic is making it's way to those gig interfaces. That is why you have congestion and packet loss. Adding additional layer 3 subnets and segmenting your users into smaller chunks and groups or moving to ten gig interfaces... I have not had great luck in lagging one gig links together due to the fact a port lag is not an equal share between ports it bases it's sharing on what it sees at layer 3 and 4 if you have that option checked. So there are still chances you can have a single gig being overun in a lag group with the other port not even close to capacity.. We are seeing this at the ten gig level in our metro core which is a 40 gig lag... Moving all the lagged ports to 100 gig...

To prove this you should be able to do a filtered capture on a stream to a client and see the packets coming in out of order when the network is loaded..

Actually those ten giga interfaces aren't bound with giga lag, they are independent lag, and yes, I set up those lag in layer3 and all network is segmented where each service is using a specific vr, for instance VR Internet and VR MCAST(PIM).
i have been taking a look at some overload on those interfaces, but nothing.
Port Link Link Rx Peak Rx Tx Peak Tx
State Speed % bandwidth % bandwidth % bandwidth % bandwidth
1:24 A 1000 6.16 9.36 51.47 68.04
1:28 A 1000 5.89 7.42 55.08 67.73
2:24 A 1000 6.88 7.95 50.87 60.31
2:28 A 1000 5.13 6.01 47.10 55.74

This is a quite curious situation, I don't have any overload, CRC Error, nothing regarding QoS profile is set up, and even so, we have this drop, and the other question, it happens just over gigabit interfaces.

New Contributor III

Updating this threat.

It really seems to be micro burst issue. I moved to 10g ports and the problem went out, but now. with peak around 8.5gbps the problem started happening again. the solution move to other switch/vendor, once that I don’t have more 10g port avaiable on this box. 

New Contributor
Have you done a show congestion command on those one gig ports... This will show you if microbursts may be filling up the buffers and thus you are dropping packets. Having any mcast video stream going into buffers is a bad thing as the buffers cause the packets to arrive at edge out of order. Out of order packets in a constant mcast stream will be dropped ...