Technical data

Customizing the Operating System
5.2 Modifying Site-Specific Startup Command Procedures
version of the file because your .COM version is damaged, copy the
.TEMPLATE file to a file with the .COM file type, and edit the copy.
5.2.1.2 Rules for Modifying Startup Command Procedures
When modifying site-specific startup command procedures, be sure to follow these
rules:
• Conform to the rules of command procedures, as described in the OpenVMS
User’s Manual.
• Keep the files in the SYS$MANAGER directory.
• Keep the file names given to the command procedures.
• Modify only the executable version of the files (with the file type .COM), not
the template version (with the file type .TEMPLATE).
• Do not modify the site-independent startup command procedure
STARTUP.COM.
• Before modifying command procedures, understand the order of startup
events. For information, see Section 5.2.2.
Caution
The startup procedures provided by Compaq should always work.
However, if you introduce an error in the startup or login procedures, you
can accidentally lock yourself out of the system. Section 4.4.2 describes a
boot procedure you can use in such an emergency.
5.2.2 Understanding the Order of Startup Events
Before modifying the site-specific startup command procedures, you should
understand the order of system startup events.
A database file named VMS$PHASES.DAT determines the order of the phases of
the startup procedure. It is a sequential list of the phases that STARTUP.COM
starts. It includes a series of four basic phases (INITIAL, CONFIGURE, DEVICE,
and BASEENVIRON) that start the operating system, followed by a series of
phases for layered products.
Caution
Do not modify VMS$PHASES.DAT. To start up correctly, the system
requires that the contents of this file remain intact.
At startup, a system performs tasks in the following order:
1. Starts the CLUSTER_SERVER process.
2. Defines logical names needed for basic operations, and installs images listed
in SYS$MANAGER:VMSIMAGES.DAT.
3. Executes SYCONFIG.COM.
5–4 Customizing the Operating System