Disk array write protection at the sub-unit level
US6041394A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 1997 |
| Grant date | Mar 21, 2000 |
| Priority date | — |
| Expiry date | Sep 24, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0689
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus, for a system having a plurality of host computers and a memory system having a disk controller with at least one mass storage device having a plurality of logical volumes, provide for write protecting the logical volumes at the controller port level. The method features changing the write protect status of one or more logical volumes, on a port level basis, in response to a first host request to change a write protect status; writing a write protect status message to a memory associated with the controller channel directors; polling, from each channel director, the memory for an unread write protect status messages; and preventing, at, for example, the channel director port level, a host connected to the channel director from writing to a protected logical volume which is write protected from that host or host port. The write protect status of that channel director, for that logical volume, remains in effect until the write protect condition for that volume has been reset. A lock mechanism must be obtained to make any changes in the logical volume write protect status.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.