2
Requirements
2-3
Installing a Deskside DPE
and each DAE’s LCC B. Do not leave an unused (that is, dangling)
cable connected to any Fibre Channel port because it may cause
excess noise on the Fibre Channel.
Addressing
Requirements
The addressing requirements vary depending on the environment,
fibre port (fabric) or fibre loop (FC-AL).
Fabric Environments
In a fabric environment, the DPE is addressed using the Source_ID
(SID) and the enclosure address (EA).
Source_ID
The Source_ID (SID) is a value that a switch in the external Fibre
Channel environment automatically assigns.
Enclosure Address (EA)
Each DPE and DAE on a back-end loop needs a unique enclosure
address (EA) that identifies the enclosure and determines disk
module addresses. The DPE has a fixed EA of 0 that you cannot
change. If you cable any DAEs to the DPE, you might want to set the
nearest DAE’s EA to 1, the next to 2, and so on. The enclosure address
is displayed in lights visible behind the front door.
Loop Environments
In an FC-AL environment, the DPE is addressed using the FC-AL
address ID and the enclosure address (EA).
Fibre Channel Arbitrated Loop Address ID (FC-AL Address ID)
Each node (such as an SP) on the Fibre Channel front-end loop must
have a unique Fibre Channel arbitrated loop address ID (FC-AL
address ID). The FC-AL protocol translates the FC-AL address ID into
an 8-bit arbitrated loop physical address (ALPA). You set the SP
FC-AL address ID using switches, as explained later in this chapter.
Enclosure Address (EA)
Each DPE and DAE on a back-end loop needs a unique enclosure
address (EA) that identifies the enclosure and determines disk
module addresses. The DPE has a fixed EA of 0 that you cannot
change. If you cable any DAEs to the DPE, you might want to set the
nearest DAE’s EA to 1, the next to 2, and so on. The enclosure address
is displayed in lights visible behind the front door.
