Disk organization

Meaning of the columns:

1	Device type as it is to be specified in BS2000 commands
2	Product name of the disk storage unit
3	Device type code
4	Change in utilization in the case of 2K when using PAM keys N requires no formatting Y requires formatting
5	Utilization: K with PAM keys NK without PAM keys
6	Minimum transfer unit between disk and main memory
7	Net capacity in 2 Kbyte units (PAM blocks) per volume
8	Track format

1	2	3	4	5	6	7	8
D3435	Disks in standard FBA format 1 2	A5	N	K	2K	variable	FBA
				NK	2K	variable	FBA

Table 1: Disk organization

1

These disks with standard FBA format are visible for BS2000 as disks with a block size of 512 bytes, e.g. disks connection to the channel of the Server Unit /390, external disks connected to the Server Unit x86. The following should be noted on the Server Unit / 390: The internal disks with the preinstalled standby system are also displayed as D3435 disks in the BS2000. In contrast to the real D3435 disks, BS2000 can neither format nor initialize the D3435 internal disks. Because the internal D3435 disks are built into the MU, they can be identified by the fact that they are generated on one of the channels 40 or 09 reserved for the MUs. Genuine D3435 disks are always connected through other channels.

2

These disks are preformatted. VOLIN simply provides them with labels. For Server Unit x86: The size and BS2000 format (K, NK2, NK4) must be defined in X2000 regardless of the preformatting and prior to initialization with VOLIN (see the “Operation and Administration” manual [5]).  Following configuration of the disk under X2000, an initialization run should always be performed using VOLIN to avoid possible discrepancies.

Notes

• Changing the transfer unit always means that formatting is required.

• Changing the allocation unit without a change of the TU is always possible without formatting.

• The following entries are only permissible for public volumes:
  
FORMAT=NK(PHYSICAL-BLOCK-SIZE=2K(ALLOCATION-UNIT=8))
FORMAT=NK(PHYSICAL-BLOCK-SIZE=2K(ALLOCATION-UNIT=64))