User Manual

SCSI Commands Reference Manual, Rev. J 149
www.seagate.com Direct Access Block commands (SPC-5 and SBC-4)
3.20.8.2 Error history directory
Whenever allowed by established error history I_T nexus constraints (see 3.20.8.1), if any, all error history device server actions return an error
history directory (see table 112). Some error history device server actions also discard the existing error history snapshot (see SPC-5) and create a
new error history snapshot (see table 110).
Table 111 defines the meaning of the combinations of values for the BUFFER ID field and the MODE SPECIFIC field for the error
history mode.
Table 110 Summary of error history directory device server actions
BUFFER ID field
Establish new error history I_T
nexus (see SPC-5)
Error history snapshot (see SPC-5)
Preserved (if exists) Created
00h
No
[a]
Yes
No
[b]
01h
No
[a]
No Yes
02h Yes Yes
No
[b]
03h Yes No Yes
[a] If no error history I_T nexus is established, a new one is established.
[b] If no error history snapshot exists, a new one is created.
Table 111 BUFFER ID field and MODE SPECIFIC field meanings for the error history mode
BUFFER ID
field
MODE SPECIFIC
field
Description
00h to 03h
000b
If a new error history snapshot is created (see table 110), vendor specific parameter data
shall be created (i.e., at least one error history directory entry (see table 115) shall contain a
BUFFER FORMAT field that is set to 00h).
001b
If a new error history snapshot is created (see table 110), current internal status parameter
data shall be created (i.e., at least one error history directory entry (see table 115) shall
contain a BUFFER FORMAT field that is set to 01h).
010b to 111b Reserved
All others 000b to 111b Reserved