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New Member

VLAN spanning two sites

I would like to stretch a subnet range across two sites that are connected by a single 100Mb link with a Cisco 2600 router at each end.

I've attached a network diagram of how my network is subnetted out. The switches at each site are 3750's and the routers are 2621's.

Basically, for the purposes of Exchange 2007 clustering, I need to have a subnet, say (let's say it's vlan50) which is available across site #1 and site #2. What configuration would I need to do on the router and the switch at each site to get this working?

New Member

Re: VLAN spanning two sites

You don't need to have each of the nodes in an Exchange 2007 cluster on the same subnet for it to work. I would actually keep them distinct to stick with your IP address convention at each site. I would however QoS the traffic between each of the exchange nodes over that 100Mbs leased line to make sure other bandwidth intensive apps or user bandwidth hogs don't take over the line and hinder exchanges's replication process.

New Member

Re: VLAN spanning two sites

I'm being told by Microsoft and even went to a Seminar where they said it had to be on the same subnet for it to work for Continuous Cluster Replication. Are you not seeing this.

Completely agree on the QOS across the link. We have a lot of traffic starting to go across the link, some important, some less important, so we will divvy up the bandwidth prioritisation as part of this project...

Thanks in advance.