System types are sometimes defined by how they access the root
(/) and /usr file systems, including
the swap area. For example, stand-alone systems and server systems mount these
file systems from a local disk. Other clients mount the file systems remotely,
relying on servers to provide these services. This table lists some of the
characteristics of each system type.
Table 6.1. Characteristics of System Types
|
System Type |
Local File Systems |
Local Swap Space? |
Remote File Systems |
Network Use |
Relative Performance |
|---|---|---|---|---|---|
|
Server |
root (
|
Yes |
None |
High |
High |
|
Stand-alone system |
root (
|
Yes |
None |
Low |
High |
|
OS Server |
| ||||
|
Diskless client |
None |
None |
root ( swap
|
High
High |
Low
Low |
|
Appliance |
None |
None |
None |
High |
High |
A server system contains the following file systems:
The root (/) and /usr file systems, plus swap space
The /export and /export/home file
systems, which support client systems and provide home directories for users
The /opt directory or file system for
storing application software
Servers can also contain the following software to support other systems:
Solaris OS services for diskless systems that are running a different release
Clients that use a different platform than the server
Solaris CD image software and boot software for networked systems to perform remote installations
JumpStart™ directory for networked systems to perform custom JumpStart installations
A networked stand-alone system can share information with other systems in the network. However, it can continue to function if detached from the network.
A stand-alone system can function autonomously because it has its own
hard disk that contains the root (/), /usr,
and /export/home file systems and swap space. Thus, the
stand-alone system has local access to OS software, executables, virtual memory
space, and user-created files.
A stand-alone system requires sufficient disk space to hold its necessary file systems.
A non-networked stand-alone system is a stand-alone system with all the characteristics just listed, except it is not connected to a network.
A diskless client has no disk and depends on a
server for all its software and storage needs. A diskless client remotely
mounts its root (/), /usr,
and /home file systems from a server.
A diskless client generates significant network traffic due to its continual need to procure OS software and virtual memory space from across the network. A diskless client cannot operate if it is detached from the network or if its server malfunctions.
For more overview information about diskless clients, see Diskless Client Management Overview.
An appliance, such as the Sun Ray™ appliance, is an X display device that requires no administration. There is no CPU, fan, disk, and very little memory. An appliance is connected to a Sun display monitor. However, the appliance user's desktop session is run on a server and displayed back to the user. The X environment is set up automatically for the user and has the following characteristics:
Relies on a server to access other file systems and software applications
Provides centralized software administration and resource sharing
Contains no permanent data, making it a field-replaceable unit (FRU)
You can determine which system types are appropriate for your environment by comparing each system type based on the following characteristics:
Centralized administration
Can the system be treated as a field-replaceable unit (FRU)?
This means that a broken system can be quickly replaced with a new system without any lengthy backup and restore operations and no loss of system data.
Does the system need to be backed up?
Large costs in terms of time and resources can be associated with backing up a large number of desktop systems.
Can the system's data be modified from a central server?
Can the system be installed quickly and easily from a centralized server without handling the client system's hardware?
Performance
Does this configuration perform well in desktop usage?
Does the addition of systems on a network affect the performance of other systems already on the network?
Disk space usage
How much disk space is required to effectively deploy this configuration?
This table describes how each system type scores in terms of each characteristic. A ranking of 1 is most efficient. A ranking of 4 is least efficient.