DEVICESCAN -n standby could work for SCSI & SAS devices too

[tconnors]

smartd.conf(5) says "-n POWERMODE" only works on ATA. My testing shows this might be true, even though smartctl(8) shows "-n POWERMODE" has experimental support for SCSI.

Either way, it shouldn't be too hard to make it work in the generic case. sdparm has a way to detect when a SCSI and SAS disk is spun down:

tconnors@pve:~$ for i in /dev/sd[b-gi-z] ; do echo $i ; sudo sdparm --command=sense $i ; done
/dev/sdb
    /dev/sdb: SEAGATE   ST4000NM0023      XMGJ
/dev/sdc
    /dev/sdc: SEAGATE   ST4000NM0023      XMGJ
/dev/sdd
    /dev/sdd: SEAGATE   ST6000NM0095      DS22
/dev/sde
    /dev/sde: SEAGATE   ST4000NM0023      XMGJ
/dev/sdf
    /dev/sdf: SEAGATE   ST6000NM0095      DS22
/dev/sdg
    /dev/sdg: TOSHIBA   MG04SCA60EE       DR07
/dev/sdi
    /dev/sdi: ATA       WDC WD10EAVS-32D  1A01
tconnors@pve:~$ for i in /dev/sd[b-gi-z] ; do echo $i ; sudo sg_start -r --pc=3 $i & done ; wait
/dev/sdb
[1] 1840017
/dev/sdc
[2] 1840018
/dev/sdd
[3] 1840019
/dev/sde
[4] 1840020
/dev/sdf
[5] 1840021
/dev/sdg
[6] 1840022
/dev/sdi
[7] 1840023
Illegal request
START STOP UNIT command failed
sg_start failed: Illegal request

tconnors@pve:~$ for i in /dev/sd[b-gi-z] ; do echo $i ; sudo sdparm --command=sense $i ; done
/dev/sdb
    /dev/sdb: SEAGATE   ST4000NM0023      XMGJ
Additional sense: Standby condition activated by command
/dev/sdc
    /dev/sdc: SEAGATE   ST4000NM0023      XMGJ
Additional sense: Standby condition activated by command
/dev/sdd
    /dev/sdd: SEAGATE   ST6000NM0095      DS22
Additional sense: Standby condition activated by command
/dev/sde
    /dev/sde: SEAGATE   ST4000NM0023      XMGJ
Additional sense: Standby condition activated by command
/dev/sdf
    /dev/sdf: SEAGATE   ST6000NM0095      DS22
Additional sense: Standby condition activated by command
/dev/sdg
    /dev/sdg: TOSHIBA   MG04SCA60EE       DR07
Additional sense: Standby condition activated by command
/dev/sdi
    /dev/sdi: ATA       WDC WD10EAVS-32D  1A01