nanog mailing list archives
Re: IP Multicast Persistent Duplicate Packet Issue
From: Jared Mauch <jared () puck nether net>
Date: Wed, 6 Apr 2022 19:45:21 -0400
You can likely set "ip pim dr-priority" to get what you want https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipmulti/command/imc-cr-book/imc_i3.html#wp1384657000 - Jared On Thu, Apr 07, 2022 at 09:07:34AM +1000, Roman Islam wrote:
Thanks Jared. Yes it is SSM. I will try to flip PIM priority and align HSRP active. My initial thought was keeping everything as it is. Can I simply flip PIM assert winner to PE1. Same way we can manually select STP root. Looks like this is probably not an option. Didn't find relevant doc on how to manipulate PIM assert winner in Cisco boxes though. Highest IP is the winner if IGP costs are the same to the source. R On Thu, Apr 7, 2022 at 3:02 AM Jared Mauch <jared () puck nether net> wrote:If this is ASM, what device is the RP? You may want to configure MSDP between PE1/PE2 to help if that’s the case, or is this SSM or something else you may want to just flip the PIM priority to make it pick what you want and see if you can tie it to your HSRP (Cisco, might I suggest VRRP so you could do dual-vendor later?) state, perhaps with EEM script to keep the config in sync if required. - JaredOn Apr 6, 2022, at 3:25 AM, Roman Islam <romislam () gmail com> wrote: Hi Everyone, Has anyone experienced a TETRA Radio application issue if underlying IPmulticast transport sends persistent duplicate packets?Here is my scenario as below: PIM is running on the MPLS L3 VPN environment. C multicast is running ona single VRF (TETRA) only. Source is running behind a dual home PE. HSRP, PIM DR path is via PE1 to the source. Anycast RP is configured with PE1 & PE2.On the receiver side there is a single PE. When I check (S,G) route onthe receiver side PE default MDT is working as expected. After the threshold exceeds it switches to the data MDT. PIM Assert mechanism winner is PE2 though (Since PE 2 has the highest IP and source is behind dual home PE with equal cost I guess).Can this be a reason for persistent duplicate multicast packets at thereceiver side; since the assert winner is PE2 but HSRP, PIM DR path is via PE1 to the source?If this is the case is there any way to manually configure the assertwinner to PE1?Roman
-- Jared Mauch | pgp key available via finger from jared () puck nether net clue++; | http://puck.nether.net/~jared/ My statements are only mine.
Current thread:
- IP Multicast Persistent Duplicate Packet Issue Roman Islam (Apr 06)
- Re: IP Multicast Persistent Duplicate Packet Issue Jared Mauch (Apr 06)
- Re: IP Multicast Persistent Duplicate Packet Issue Roman Islam (Apr 06)
- Re: IP Multicast Persistent Duplicate Packet Issue Jared Mauch (Apr 06)
- Re: IP Multicast Persistent Duplicate Packet Issue Roman Islam (Apr 06)
- Re: IP Multicast Persistent Duplicate Packet Issue Jared Mauch (Apr 06)