Installation guide

For more information about how the DIGITAL UNIX system and network
management environment compares to the same environment on ULTRIX
systems, see Chapter 4.
1.2.5 Data Interoperability
In many cases, you can exchange data easily between DIGITAL UNIX and
ULTRIX systems. For example, you can mount an ULTRIX file system on a
DIGITAL UNIX system. (For information about performing this task, see
Section 5.1.) In addition, you can use DIGITAL UNIX commands to read
tapes you create with the ULTRIX tar and pxtar commands. (For
information about using these commands on a DIGITAL UNIX system, see
Section 5.3.) You can also use the cpio and ltf commands to read and
write tape archives. You can use the dump command on an ULTRIX system
and the restore command to restore the dump on a DIGITAL UNIX
system. In addition, you can use TCP/IP network copying facilities.
Users on an ULTRIX system can also exchange data with a DIGITAL
UNIX system provided that files are less than 2 gigabytes (GB) in size.
1.2.6 Symmetric Multiprocessing
The DIGITAL UNIX system supports Symmetric Multiprocessing (SMP).
SMP is a modification to the kernel that allows multiple processors to
execute the kernel code simultaneously. SMP activity is accomplished
safely by means of locks, which are used to control the concurrent access of
shared data structures within the kernel.
The SMP software on DIGITAL UNIX systems has a high degree of
commonality with the ULTRIX SMP software. You can migrate your
ULTRIX SMP applications to DIGITAL UNIX systems as long as you
ensure that the applications conform to the migration information in this
manual. There are no specific SMP migration considerations for users or
system managers, and the only programming considerations are:
• ULTRIX SMP applications can use two system calls, startcpu and
stopcpu, which have no equivalent calls on DIGITAL UNIX systems.
• ULTRIX SMP applications employ the cpustat command to display
information about the use and state of each CPU in a SMP system. The
DIGITAL UNIX system employs the kdbx debugger for the same
purposes. See kdbx
(8) for more information.
1–8 Introduction to Migrating from ULTRIX to DIGITAL UNIX Systems