Chapter 1 HPSS Basics
HPSS Installation Guide September 2002 33
Release 4.5, Revision 2
whereby a user's access permissions to an HPSS bitfile are specified by the HPSS bitfile
authorizationagent, the Name Server. These permissions are processed by the bitfile data
authorizationenforcement agent, the Bitfile Server. The integrity of the access permissions
iscertified by the inclusion of a checksum that is encrypted using the security context key
shared between the HPSS Name Server and Bitfile Server.
•Logging. A logging infrastructure component in HPSS provides an audit trail of server
events. Logged data includes alarms, events, requests, security audit records, status
records, and trace information. Servers send log messages to a Log Client (a server
executingon each hardware platform containing servers that use logging). The Log Client,
which may keep a temporary local copy of logged information, communicates log
messages to a central Log Daemon, which in turn maintains a central log. Depending on
the type of log message, the Log Daemon may send the message to the SSM for display
purposes. When the central HPSS log fills, messages are sent to a secondary log file. A
configuration option allows the filled log to be automatically archived to HPSS. A delog
function is provided to extract and format log records. Delog options support filtering by
time interval, record type, server, and user.
•Accounting.The primary purpose of the HPSS accounting system is to provide the means
tocollect information on usage in order to allow a particular site to charge its users for the
use of HPSS resources.
Forevery account index, the storage usage information is written out to an ASCII text file.
Itis the responsibility of the individual site to sort and use this information for subsequent
billing based on site-specific charging policies. For more information on the HPSS
accounting policy, refer to Section 1.3.7.
1.3.5 HPSS User Interfaces
Asindicated in Figure 1-3, HPSS provides the user with a number of transfer interfaces as discussed
below.
•File Transfer Protocol (FTP).HPSS provides an industry-standard FTP user interface.
Becausestandard FTP is a serial interface, data sent to a user is received serially. This does
notmean that the data within HPSS is not stored and retrieved in parallel; it simply means
that the FTP Daemon within HPSS must consolidate its internal parallel transfers into a
serialdata transfer to the user. HPSS FTP performance in many cases will be limited not by
the speed of a single storage device, as in most other storage systems, but by the speed of
the data path between the HPSS FTP Daemon and the user’s FTP client.
•NetworkFile System (NFS). The NFS server interface for HPSS provides transparent access
toHPSS name space objects and bitfile data for client systems through the NFS service. The
NFSimplementation consists of an NFS Daemon and a Mount Daemon that provide access
toHPSS, plus server support functions that are not accessible to NFS clients. The HPSS NFS
servicewill work with any industry-standard NFS client that supports either (or both) NFS
V2 and V3 protocols.
•ParallelFTP (PFTP). The PFTP supports standard FTP commands plus extensions and is
builtto optimize performance for storing and retrieving files from HPSS by allowing data
tobe transferred in parallel across the network media. The parallel client interfaces have a
syntax similar to FTP but with some extensions to allow the user to transfer data to and
from HPSS across parallel communication interfaces established between the FTP client