10 discover address (adisc), Discover address (adisc) – Seagate Fibre Channel Interface User Manual
Page 105
Fibre Channel Interface Manual, Rev. D
91
9.2.10
Discover Address (ADISC)
Discover Address (ADISC) is sent by an initiator to a drive after loop initialization to verify addresses have not
changed or to verify the drive was able to obtain the hard address select through the interface connector (SEL
Lines) during loop initialization.
The ADISC allows the drive to compare the initiator’s address and Port Name with previous login values. If
after the loop initialization process the address and Port Name pair provided by the initiator does not match the
login values, the initiator is implicitly logged out.
Field definitions (listed alphabetically)
Hard Address of Originator
This is the 24 bit NL_Port Identifier. The lower 8 bits are the AL_PA the initiator attempts to acquire in the LIHA sequence
during loop initialization. If the initiator does not have a hard address, this 24 bit field is zeros. If the initiator has a hard
address and is able to acquire it during the loop initialization process, the Hard Address and N_Port ID fields of the ADISC
will be the same.
If ESI activity is underway when the request for the hard address is received, the drive shall use the last known value of the
hard address before the current ESI activity started. For more information on ESI, refer to Section 10.5.
LS Command Code (Link Services Command Code)
52h
ADISC Payload.
Table 49:
ADISC Payload
Bit
Byte
7
6
5
4
3
2
1
0
0
0
1
0
1
0
0
1
0
1
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
3
0
0
0
0
0
0
0
0
LS Command Code
4
Reserved
5
(MSB)
Hard Address of Originator
6
7
(LSB)
8
(MSB)
Port Name of Originator
:
15
(LSB)
16
(MSB)
Node Name of Originator
:
23
(LSB)
24
Reserved
25
(MSB)
N_Port ID of Originator
26
27
(LSB)
Table
number