| .. SPDX-License-Identifier: GPL-2.0 | 
 |  | 
 | ====================================== | 
 | Linux SCSI Disk Driver (sd) Parameters | 
 | ====================================== | 
 |  | 
 | cache_type (RW) | 
 | --------------- | 
 | Enable/disable drive write & read cache. | 
 |  | 
 | ===========================   === ===   ===========   ========== | 
 |  cache_type string            WCE RCD   Write cache   Read cache | 
 | ===========================   === ===   ===========   ========== | 
 |  write through                0   0     off           on | 
 |  none                         0   1     off           off | 
 |  write back                   1   0     on            on | 
 |  write back, no read (daft)   1   1     on            off | 
 | ===========================   === ===   ===========   ========== | 
 |  | 
 | To set cache type to "write back" and save this setting to the drive:: | 
 |  | 
 |   # echo "write back" > cache_type | 
 |  | 
 | To modify the caching mode without making the change persistent, prepend | 
 | "temporary " to the cache type string. E.g.:: | 
 |  | 
 |   # echo "temporary write back" > cache_type |