Can I have different publishers and one subscriber in replication?
Yes it is possible to have many publishers and only one subscriber. You can also have one publisher and many subscribers. So in your case you will be able to publish from City1 and City2 and subscribe only City1 on those publishers. You can use this link to have an overview of the replication engine and how to setup it. http://technet.microsoft.com/en-us/library/ms151198.aspx

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