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How can you use this feature? Some use cases are really obvious. It´s a natural match for disaster recovery. The Sun Cluster Geographic Edition even supports this kind of remote mirror out of the box to do cluster failover with wider distances than just a campus. But it´s usable for other jobs as well, for example for migrations to a new datacenter, when you have to transport a large amount data over long distances without a time window for a longer service interruption.

Andrew S. Tannenbaum said "Never underestimate the bandwidth of a truck full of tapes hurling down the highway". This sounds counterintuitive at the first moment, but when you start to think about it, it´s really obvious.

A new scenario: Okay, the filesystem gets replicated now. Let´s assume that we use /dev/rdsk/c1d0s1 for a database. The filesystem and the database partition are used from the same application and it´s important, that the metadata in the database an the binary objects are in sync even when you switched over to the remote site, albeit it´s acceptable to lose the last few transactions, as both sites are 1000km away from each other and synchronous replication is not an option.

One of the most essential tasks when configuring disaster recovery mechanism is training the procedure. Thus let´s test the switch into our remote datacenter. We will simulate a failure now. This will show that the data really get´s replicated to a different system

After this short introduction in the theory of AVS Remote mirror, we will set up such an replication between two hosts.

Some words about Sun StorageTek Availability Suite at first: We´ve opensourced the product quite a while ago. While it´s a commercial product for Solaris, we´ve integrated it into Solaris Express Community Edition and Developer Edition.

Solaris was designed with commercial customers in mind. Thus this operating environment has some capabilities that are somewhat useless for the soho user, but absolutly essential for enterprise users. One of this capabilities is remote replication of disk volumes. Imagine the following situation. You have a database and a filesystem for a central application of your company. The filesystem stores binary objects (for example images or something like that). The application is so important for your company, that you plan to build a replicated site. And now your problems start.