05-20-2009 09:35 AM
Hi,
I have to run PIM-SM and PIM-SSM based both in Core. This is purely due to multivendor enviroment.
When I have all customer sites on cisco, i will run PIM-SSM ( default +data) and when i have multivendor in picture will run PIM-SM ( default) for specific customer. This will purely product team driven.
Now, I have to make sure that i use proper different Multicast group for both.
I have in mind that
1. PIM-SM - 239.192.0.0/16 range.
where 239.192.1.1 - default mdt, 239.192.2.0/24 - DATA MDT per customer
same way second customer 239.192.1.2 - default , 239.192.3.0/24 - DATA MDT
2. PIM-SSM : 239.232.0.0/16
customer -1
239.232.1.1 - default mdt
239.232.2.0/24 - data mdt
customer-2
239.232.1.2 - default mdt
293.232.3.0/24- data mdt ..so on.
With this, I have following configuation :
ip pim rp-address 1.1.1.1 SM-RANGE
ip pim ssm range SSM-RANGE
ip access-list standard SSM-RANGE
permit 239.232.0.0 0.0.255.255
ip access-list standard SM-RANGE
permit 239.192.0.0 0.0.255.255
ip vrf VPN-A
description A Customer using MVPN SM
rd 65000:65003
route-target both 65000:65000
mdt default 239.192.1.1
mdt data 239.192.2.0 0.0.0.15 threshold 1
ip vrf VPN-B
description A Customer using MVPN SSM
rd 65000:65011
route-target both 65000:65000
mdt default 239.232.1.1
mdt data 239.232.2.0 0.0.0.15 threshold
ip multicast-routing
ip multicast-routing vrf VPN-A
ip multicast-routing vrf VPN-B
Is this looking corect ? I have one doubt is, the DATA MDT range used for PIM-SM based solution should be in SM ACL or SSM ACL ??
Any suggestion on Multicast addressing for my requirment ? I would apprcieate the help !!
Regards,
Chintan
Regards,
Chitnan
Solved! Go to Solution.
05-21-2009 03:13 AM
Chintan,
Assuming you will always use PIM SSM for the DATA MDT, you can use the same pool on all PEs as PIM SSM uses both the multicast address and the source address to identify a given multicast stream. So using the same pool on a all PEs is not an issue as long as the pool is unique on the PE.
Regards
05-21-2009 05:18 AM
Hi,
Let's say you use PIM-SM for the Data-MDT and you have the same pool configured for the same Multicast Domain or mVPN.
If two PEs connected to two different customer sources using different groups choose the same Data-MDT group, each PE joining this Data-MDT will receive both traffic even if their receivers are interested only with one customer group.
If you let the PEs to switchover to the SPT, they could also choose the wrong source PE.
Here is an extract from Rozen draft about this issue:
"
7.3. Use of SSM for Data MDTs
The use of Data MDTs requires that a set of multicast P-addresses be
pre-allocated and dedicated for use as the destination addresses for
the Data MDTs.
If SSM is used to set up the Data MDTs, then each MD needs to be
assigned a set of these of multicast P-addresses. Each VRF in the MD
needs to be configured with this set (i.e., all VRFs in the MD are
configured with the same set). If there are n addresses in this set,
then each PE in the MD can be the source of n Data MDTs in that MD.
If SSM is not used for setting up Data MDTs, then each VRF needs to
be configured with a unique set of multicast P-addresses; two VRFs in
the same MD cannot be configured with the same set of addresses.
This requires the pre-allocation of many more multicast P-addresses,
and the need to configure a different set for each VRF greatly
complicates the operations and management. Therefore the use of SSM
for Data MDTs is very strongly recommended.
"
So the best design in your case is to have PIM-SM (without switchover to the SPT) for the default-MDT and PIM-SSM for the Data-MDT as already explained by Harold. This should be supported by all vendors.
Regarding your SLA, if you are using anycast RP, your convergence time is the same as for PIM-SSM, it relies only on the speed of your IGP to converge.
HTH
Laurent.
05-20-2009 06:13 PM
Chintan,
Picking a different approach for different customers will make this network more complicated to provision, support and troubleshoot.
I would suggest you pick the one approach that fits all vendors (lowest common denominator) and that you use it for all customers. This will probably save lots of headaches.
Regards
05-20-2009 10:52 PM
Hi Hritter,
I agree with you but problem is we have some of customer requirments like fast convergance where PIM-SM doesn't give be nefit due to RP/MSDP Infra and so we might have to use PIM-SSM.
But there are some customers who have specially not specific SLA and some of sites on DSL for which BRAS doesn't support PIm-SSM and we are forced to give PIM-SM . that's why we feel to keep two approach and going foraward i would like to keep only PIM-SSM once vendor support this....
I am still under evaluation stage and will also have word with our cisco AS team.
Many thanks for your feedback.
Regards,
Chintan
05-20-2009 06:32 PM
Hi,
It works for PIM SSM because the source will be different so you can use the same Data-MDT pool for the same mVPN on different PE.
But with PIM-SM, you will not be able to differentiate two different sources for which their attached PEs chose the same Data-MDT so you need a pool per mVRF instead of per mVPN
Also your configuration looks correct.
HTH
Laurent.
05-20-2009 10:56 PM
Hi Laurent,
When you say PIm-SM, I will neer pool per mVRF instead of per mVPN.
Does it mean that if i have 100 sites say connected to 20 PE in network , I will have to use total 20 different DATA POOL.
like : 239.192.2.0/24 ---239.192.21.0/24 ?
Regards,
Chintan
05-20-2009 11:08 PM
Hi Chintan
You can use the same pool across all the PE. Because data mdt will be used as a single per PE. SO if you are using /24 pool it means 255 PE can be connetced for same mVPN custmer.
regards
shivlu jain
05-20-2009 11:20 PM
Hi Shivlu,
I had a same understanding but as per laurent it is not a case , as he says for PIM-SM, you will have to use different pool per mVRF not per mVPN.
Am I understanding something wrong here ?
REgards,
Chintan
05-20-2009 11:46 PM
Hi Chintan
It is truly said by laurent.
Please check the section 4.1 of the given link
http://tools.ietf.org/html/draft-rosen-vpn-mcast-07
regards
shivlu jain
05-21-2009 03:13 AM
Chintan,
Assuming you will always use PIM SSM for the DATA MDT, you can use the same pool on all PEs as PIM SSM uses both the multicast address and the source address to identify a given multicast stream. So using the same pool on a all PEs is not an issue as long as the pool is unique on the PE.
Regards
05-21-2009 03:42 AM
Hi Hritter,
But if we use PIM-SM for DATA MDT aswell, What Laurent says is applicable and for same customer if they have 10 VRF ( i.e.PE) i have to use 10 different Multicast group range for DATA MDT.
But even I use PIM-SM for Default but DATA on PIM-SSM , What you says would be more sclable solution.
Am i correct ?
05-21-2009 01:37 AM
Hi Laurent
It would be better if you explain with the help of some example so that we can get the proper understanding.
regards
shivlu jain
05-21-2009 04:47 AM
Hi,
Can you direct to any link explaining your input in little detail ?
Regards,
Chintan
05-20-2009 09:26 PM
Hi Chintan
The configuration looks fine. If the customer is provisioned with SSM then data and default mdt shoudl be a part of SSM acl. If the customer is provisioned with SM then data and default mdt should be configured in SM acl.
The main logic is that mrouting of data and default should available in global mrouting table.
regards
shivlu jain
05-21-2009 05:18 AM
Hi,
Let's say you use PIM-SM for the Data-MDT and you have the same pool configured for the same Multicast Domain or mVPN.
If two PEs connected to two different customer sources using different groups choose the same Data-MDT group, each PE joining this Data-MDT will receive both traffic even if their receivers are interested only with one customer group.
If you let the PEs to switchover to the SPT, they could also choose the wrong source PE.
Here is an extract from Rozen draft about this issue:
"
7.3. Use of SSM for Data MDTs
The use of Data MDTs requires that a set of multicast P-addresses be
pre-allocated and dedicated for use as the destination addresses for
the Data MDTs.
If SSM is used to set up the Data MDTs, then each MD needs to be
assigned a set of these of multicast P-addresses. Each VRF in the MD
needs to be configured with this set (i.e., all VRFs in the MD are
configured with the same set). If there are n addresses in this set,
then each PE in the MD can be the source of n Data MDTs in that MD.
If SSM is not used for setting up Data MDTs, then each VRF needs to
be configured with a unique set of multicast P-addresses; two VRFs in
the same MD cannot be configured with the same set of addresses.
This requires the pre-allocation of many more multicast P-addresses,
and the need to configure a different set for each VRF greatly
complicates the operations and management. Therefore the use of SSM
for Data MDTs is very strongly recommended.
"
So the best design in your case is to have PIM-SM (without switchover to the SPT) for the default-MDT and PIM-SSM for the Data-MDT as already explained by Harold. This should be supported by all vendors.
Regarding your SLA, if you are using anycast RP, your convergence time is the same as for PIM-SSM, it relies only on the speed of your IGP to converge.
HTH
Laurent.
05-21-2009 05:37 AM
Hi Laurent,
Many thanks for excellent explanation on pointing on draft-rosen section. Now I understood well.
I will change my configuation to keep PIN-SM ACL for only Default MDT and PIM-SSM for DATA MDT.
And also can use PIM-SSM Default MDT from same SSM based range.
Sorry for multiple mails but i understood well now.
Thanks Hritter for your help too !!
Regards,
Chintan
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