The asynchronous or long distance mirroring function for the SVC is called Global Mirror, and will fill out the replication portfolio for the SVC, which already features snapshotting and local or synchronous mirroring functions.
Heterogeneous replication is a key selling point for any virtualization system. IBM said yesterday, however, This announcement delays the availability of Global Mirror by only a couple of months so we don’t believe it will have a major impact [on SVC sales].
As a fill-in, IBM had been recommending that customers use the long distance mirroring in start-up Kashya Inc’s replication software. But Kashya was bought by EMC Corp in May this year, at which point IBM presumably instantly ceased from promoting the Kashya software. IBM said that Global Mirror was never planned to be based on any software OEM’ed from Kashya.
EMC has promised that before the year’s end the Kashya suite of replication functions will be built into its Invista virtualization product.
This means that Invista will gain a full suite of replication functions and possibly Kashya-inspired CDP features at around the same time that IBM fills out the replication suite for the SVC. Currently, Invista only offers data migration functions, and has no mirroring or snapshotting data replication functions designed for disaster recovery.
Launched in 2003, the in-band appliance based SVC passed 2,000 customers this summer. Invista was launched around twelve months ago, and runs on a smart SAN switch. EMC is not yet declaring how many customers it has won for Invista, or naming any reference customers.