PQ

Packet

The basic unit of information to be transferred over the network.

Parallel

Simultaneous. Usually applied to a RAID-3 environment where a block of data is transferred by dividing it into smaller blocks, accessing all drives at once and simultaneously transferring the data.

Parent process

The main, or primary, program or first process loaded into memory. A parent process forks a child process, which, in turn, can fork other processes.

Parity

A method used by RAID5 configurations to provide data redundancy. Typically, a RAID5 configuration stores data blocks and parity blocks. In the case of a missing data block, the missing data can be regenerated using the other data blocks and the parity block.

Partition table

This identifies a disk's slices, the slice boundaries (in cylinders), and the total size of the slices.

Password aging

A system parameter set by the system administrator in the /etc/default/password file that requires users to change their passwords after a certain number of days.

Password encryption

The reversible transformation of a user's password from the original (the plaintext) to a difficult-to-interpret format (the ciphertext). It is done as a mechanism for protecting its confidentiality. Encryption uses an encryption algorithm. The encrypted password consists of 13 characters chosen from a 64-character alphabet.

Patchlist file

Specifies a file containing a list of patches to install.

PCFS (Personal Computer File System)

Allows read and write access to data and programs on DOS-formatted disks that are written for DOS-based personal computers.

Physical device name

This represents the full device pathname in the device information hierarchy. Physical device names uniquely identify the physical location of the hardware devices on the system and are maintained in the /devices directory. The physical device name contains the hardware information, represented as a series of node names separated by slashes that indicate the path to the device.

Platform group

This is a general term used to group Sun systems together based on their hardware architecture. To determine the platform group that your Sun system belongs to, use the uname -m command. The system will respond with the platform group and the platform name for your system.

Port

See network port and hardware port.

POST (power-on self-test)

When a system is turned on, the monitor runs a POST that checks such things as the hardware and memory on the system. If no errors are found, the automatic boot process begins.

Power management software

Provided in the Solaris environment to automatically save the state of a system and turn it off after it is idle for 30 minutes. On newer systems that comply with the EPA's Energy Star guidelines, the power management software is installed by default. You are then prompted after rebooting to enable or disable the power management software.

Primary group

Each user is assigned to a primary group when they log in. This is the group the operating system will assign to files created by the user.

Print client

A remote system that sends print requests to a print server.

Print daemon

A system process that supports printing activities.

Print Manager

A graphical user interface used to manage printers in a name service environment.

Print scheduler

The LP print service has a scheduler daemon called lpsched. This print scheduler daemon updates the LP system files with information about printer setup and configuration. This dameon schedules all of the local print requests on a print server. It tracks the status of printers and filters on the print server.

Print server

A system that has a local printer connected to it, makes the printer available to other systems on the network, and provides spooling for the client's print requests.

Printer class

Several locally attached printers that are put into a group. A printer class is helpful if you have several printers sitting next to each other, and it doesn't matter which printer your job goes to.

Process

A program in operation.

PROCFS (Process File System)

A file system that resides in memory and contains a list of active processes.

Profile

A JumpStart configuration file that defines how the Solaris software is installed on the JumpStart client if a system matches the rule. Every rule in the rules file specifies a profile that defines how a system is to be installed when the rule is matched. You usually create a different profile for every rule. However, the same profile can be used in more than one rule. See also rules file and rights profile.

PROM (Programmable Read-Only Memory)

A permanent memory chip that is programmed, or filled, by the customer rather than by the chip manufacturer. It differs from a ROM, which is programmed at the time of manufacture. PROMs have been mostly superseded by EPROMs, which can be reprogrammed.