Redundancy for the access device connected to two routers

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Aug 30th, 2008
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Please find the attachment for the network diagram. DSLAM is connected to the layer 2 access switch SW3. SW3 has two uplinks, one goes to SW1 and other goes to SW2. SW1 and SW2 have to act as Layer 2 switches. SW1 has the uplink to one of the PE and SW2 has the uplink to other PE. DSLAM provides Internet, Voice and IPTV. Internet is using PPPoE. So there is an l2 tunnel from DSLAM to BRAS which is connected to the MPLS. DSLAM will use only one vlan for all the access PVCs. Voice is provided using L3 vpn. DSLAM should access the VOICE VPN via both PE routers. IPTV is using multcast. PIM is configured till PE routers. Requirement is as follows,

1)Failure of a link between switches and routers should not affect any services.

2) Failure of a switch or a router should not affect the any services.

What is the solution to archive the requirements?



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Marwan ALshawi Sun, 08/31/2008 - 01:07
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if each router in difrent vlan

use PVST

make sw1 primary root brig for the vlan connected to it PE and secondary in sw2

the same on sw2

add aditional uplink from each router to the other switch

also from sw1 and 2 to 3 make the uplinks as etherchannel of two physical links

so that in case of any of those links fails the other will continue

if helpful rate


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