Remote dual copy system.

摘要

A remote dual copy system 300 incorporates dynamically modifiable ports on the storage controllers such that those ports can operate either as a control unit link-level facility or as a channel link-level facility. When configured as a channel link-level facility, a primary storage controller 322 can appear as a host processor to a secondary storage controller 332. Using dynamic switches 305, 315 coupled between primary and secondary sites, fewer ESCON communication links 351 are required since the ESCON communication links can function either as a channel or as storage controller communication link.