Can you explain to me if it's possible to connect a mainframe IBM to a SAN to make a remote copy? We are thinking of using XRC and FICON channel protocol. Our remote site is over 70Km.
Sure is. You can connect the FICON channels out of your mainframe to a SAN witch that supports the FICON protocol. I know McData currently supports this and in the near future you will be able to have FC and FICON ports in the same switch. (You cannot use FC zoning with the FICON ports yet). The other switch vendors will also be supporting FICON.
Extended Remote Copy (XRC) is a mainframe remote copy solution that lets you remote copy data that spans multiple storage arrays. Unlike UNIX and Windows servers, mainframes can be configured with thousands of volumes. All the writes to these volumes can then be copied through an extender to a storage array at the disaster site.
I don't think FICON is supported as the remote copy medium for XRC at this time. You can use ESCON for the remote copy links to something like a CNT Ultranet or Inrange extender for connection over IP or DWDM to the remote site. As an alternative, if your storage subsystem supports Fibre Channel remote copy, you can use FICON as the storage channels into the storage array (you don't even need a switch for this, just direct connect, then use an FC port on the storage array as an initiator and connect the FC ports to lower cost CNT edge, Inrange 9801 or Nishan extenders to the remote site. These newer extenders provide great data compression and will allow you to go greater distances using a less expensive leased line.
For 70Km distances, you are reaching the limit of sync remote copy distances. Expect about 1ms of delay for every 100 miles (theoretical) but in real life expect about 1ms for every 25 miles. When you lease a line for remote copy of data, the link is never laid as the crow flies (in a straight line) to the other location. A 70Km distance between sites may mean 140Km for the link length since it may need to be routed over bridges and under tunnels. You may want to consider using async copy for XRC.
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This was first published in November 2002