Steps for controlling where DirMaint creates minidisks

Before you begin

Make sure the DIRMAINT virtual machine is logged off. You need to log onto the 7VMDIR20 virtual machine.

About this task

The EXTENT CONTROL file tells DirMaint where to allocate minidisks. The file is divided into sections. Each section can occur only once.

:REGIONS.: Identifies DASD extents on individual devices that can be used for minidisk allocation.
:GROUPS.: Allows you to group devices by name and refer to them by a single name. For example, you can create a group called SYSTEM for minidisks related to system user IDs, or a group called LINUX for minidisks related to virtual machines for Linux®. Grouping allows you to separate user minidisks from system-related minidisks.
:SSI_VOLUMES.: Can be used if you are operating in an SSI cluster. This section defines which volumes DirMaint uses when cloning a new SUBCONFIG entry from an existing SUBCONFIG entry.
:EXCLUDE.: Gives you the ability to map some or all of a user's extents as excluded. DirMaint prevents existing minidisks from being overlapped during allocation procedures. If you would like to disable this facility for a particular minidisk, specify it within the :EXCLUDE. section. When determining free space, DirMaint does not take into account the extents of excluded devices.
Note: If the minidisk address in the entry is less than 4 digits, pad the address with one or more leading zeros to create a 4-digit address.
:AUTOBLOCK.: Entries are used by the DirMaint machine to calculate the number of cylinders or blocks to allocate with some automatic allocation methods. As shipped, this section is empty. Modifications should be made to this section only if your installation is using a device type not defined in the AUTOBLK DATADVH file.
:DEFAULTS.: Defines the maximum size for various DASD devices. As shipped, this section is empty. Modifications should be made to this section only if your installation is using a device type not defined in the DEFAULTS DATADVH file.

Procedure

Edit the EXTENT CONTROL file on the J-disk.
```
xedit extent control j
```
Find the section labelled :REGIONS..
From the XEDIT command line, type this command and press the Enter key:
```
====> /:regions.
```

Move the cursor to the prefix area for the line containing *RegionID. Type i in the prefix area and press the Enter key:

00034 * ******************************************************
00035 :REGIONS.                                               
i       *RegionId     VolSer     RegStart   RegEnd       Type

Move the cursor to the body of the blank line and type a statement with this pattern:
```
RegionId VolSer RegStart RegEnd Type
```
where

RegionId

Is the name of the region. Region names must be unique. If a region entry shares the same name with another region entry, the first record is used, the second entry is ignored. Region names may consist of the characters A-Z, 0-9, #, @, and $. DirMaint requires that this field be eight characters or less.

VolSer

Is the volume label of the real DASD. This value represents the value placed into volser field on any minidisks generated from this region. Volume IDs supported by DirMaint consist of a maximum of six characters A-Z, 0-9, #, @, and $. VolSer must be unique.

RegStart

Is the starting cylinder for this region.

RegEnd

Is the ending cylinder for this region.

Type

Is the device type of the DASD. You can use default types from DEFAULTS DATADVH file or you may define other types in the :DEFAULTS. section of the EXTENT CONTROL file (see step 11.)
Example: The following statement labels an entire 3390-03 with a volume label LINUSR1 as LINUX01:
```
LINUX01 LINUSR1 001 END 3390-03
```
(END is a special keyword specifying the last cylinder.)
Repeat step 4 for all the volumes you need for your Linux virtual servers.
Note: The region names must be unique.
Immediately after the volume statements for Linux virtual servers, add this statement for creating minidisks for other virtual machines.
```
SSIU01 SSIU01 1 END devtype
```
where devtype is the device type of volume SSIU01.
Move the cursor to the prefix area for the line containing *GroupName.
Type i2 in the prefix area and press the Enter key:
```
00121 :GROUPS.                
i2      *GroupName RegionList 
```
Type these two lines:
```
GRPLNX (ALLOCATE ROTATING)
GRPLNX LINUX01
```
If you have additional regions, add those region IDs to the second line.
Example:
```
GRPLNX LINUX01 LINUX02 LINUX03
```
Move the cursor to the prefix area for the line with * ENTRY_NAME ADDRESS, type i5 in the prefix area, then press the Enter key:
```
00139 :EXCLUDE.
i5    * ENTRY_NAME ADDRESS 
00141 :END.            
```

Type these five lines:

MAINT*   012*      
MAINT*   013*      
PMAINT   013*      
SYSDUMP1 012*      
SYSDMP*  012*

If you have specified any device type that is not listed in the DEFAULTS DATADVH file, define it in the :DEFAULTS. section.
Place your cursor into the blank line inside the :DEFAULTS. section, then type a statement with the following pattern:
```
ttttmmmm cyl|blk
```
where

tttt

Specifies the device type associated with this default entry.

mmmm

Specifies an index string used when cross checking a :REGIONS. entry with a :DEFAULTS. entry. The index string should consist of the following characters: A-Z, 0-9, #, @, $, or – (dash) without embedded blanks. The index string can be from 1- to 4-characters long.

cyl/blk

Specifies the maximum allocatable cylinder (for CKD devices) or block (for FBA devices) on this device.
Example:
```
3380-05	665
3380lnx1	257
```
Note: If a :REGIONS. entry specifies a ttttmmmm of 3380-05, DirMaint considers cylinder 664 as the maximum allocatable cylinder.
Save the file.
From the XEDIT command line, type this command and press the Enter key:
```
====>  file
```

Results

Your file should look similar to this:

 EXTENT   CONTROL  J2  V 254  Trunc=254 Size=89 Line=35 Col=1 Alt=0             
====>                                                                           
   35 :REGIONS.                                                                 
   36 *RegionId  VolSer    RegStart      RegEnd  Dev-Type  Comments             
⋮
   46 LINUX01   430LIN           1         END  3390-03                         
⋮
   57 720W02    720W02           1         END  3390-03                         
   58 :END.                                                                     
   59 :GROUPS.                                                                  
   60 *GroupName RegionList                                                     
   61 DVHUSR    (ALLOCATE ROTATING)                                             
⋮
   65 GRPLNX    (ALLOCATE ROTATING)                                             
   66 GRPLNX    LINUX01 LINUX02 LINUX03                                         
⋮
   71 :END.                                                                     
   72 :EXCLUDE.                                                                 
   73 * UserId Address                                                          
   74   MAINT*   012*                                                           
   75   MAINT*   013*                                                           
   76   PMAINT   013*                                                           
   77   SYSDUMP1 012*                                                           
   78   SYSDMP*  012*                                                           
   76 :END.                                                                     
⋮

What to do next

Continue to the next procedure.