OSPF on ISC port in mlag

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Can we run OSPF on isc vlan ? how the fail over will happen if layer 3 link connected to VRRP Master fail and we have only ISC port connection to VRRP backup
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gajanan

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Posted 9 months ago

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Jacob, Praveen, Employee

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The ISC VLAN is only provisioned to carry inter MLAG-peer control traffic and ipforwarding is almost always never enabled on an ISC VLAN. Which layer 3 link are you talking about here? 
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Grosjean, Stephane, Employee

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I agree with Jacob, the ISC VLAN cannot be enabled for ipforwarding. However you could have a L3 vlan using the ISC PORTS.

That being said, I'm not sure to understand what you want to do. With MLAG, you can run VRRP in Master/Backup typical state, or use Fabric Routing to act in Master/Master. Losing the ISC connection is always a bad thing, that's why we recommend to have a LAG.
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gajanan

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Hi guys.. thanks for your reply.. appreciate it..i mean Layer 3 connection between vrrp master n backup switch...we had issue last time when isp Link on vrrp master failed and traffic black holed at VRRP master switch as it dint had any l3 connection with vrrp backup
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Grosjean, Stephane, Employee

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Then, what you need is to track the interface and failover VRRP when it's down. Look for VRRP Tracking in the User Guide, to confirm this is what you need.
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gajanan

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thanks for ur reply..we have decided to use dedicated layer 3 connection between vrrp master and backup