IBM RS/6000 SP, Руководство по определению проблем

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This soft copy for use by IBM employees only.
9.6 Managing Print Services
Print management tools are supplied with PSSP 2.1 to shift printing functions
from the nodes to a print server, eliminating the need to maintain and support
print queues on a large number of nodes. An RS/6000 SP node is designed to
use a unique remote host, PRINT_HOST, as a print server.
For further information on the use of the SP Print Management System see
Chapter 16 “Managing Print Service” in the
IBM RISC System/6000 Scalable
POWERparallel Systems: Administration Guide, GC23-3897.
9.6.1 Using Print Services
The SP Print Management System can run in either
Open, or Secure Mode.
For Secure Mode set print_config = secure and p r i n t _ i d = p r t i d . For Open
Mode, set
print_config = open . Use either smitty site_env_dialog
or
spsitenv
to set these values.
Secure Mode requires only one user ( prtid) to have
rsh
privileges on the print
server. This user account is responsible for transferring all print jobs to the print
server.
Open Mode requires all users who need access to a printer to have
rsh
privileges on the print server. Therefore, these users can execute other
commands on the print server through
rsh
as well, which could pose a security
exposure.
If print_config = secure or open, then the following sequence will configure Print
Services:
1. /etc/rc.sp is started from /etc/inittab
2. /usr/lpp/ssp/install/bin/services_config is called from /etc/rc.sp
3. /usr/lpp/ssp/install/bin/print_config is called from services_config
The print_config script copies all the print commands in /usr/bin to cmd.AIX.
The base AIX print commands are then linked to /usr/lpp/ssp/bin/pmswitch. If
Secure Mode is used, then /usr/lpp/ssp/bin/pmbec has setuid permission added.
9.7 Managing NTP
A mechanism to synchronize clocks is needed because the RS/6000 SP nodes do
not have system batteries. Network Time Protocol (NTP) is used as the default
mechanism, on the RS/6000 SP system, to achieve this. The RS/6000 SP uses
NTP to set the time at system initialization and to synchronize time-of-day clocks
on the Control Workstation and nodes. Other time-service protocols (timed or
Digital Time Service) may be used instead of NTP.
For further information on NTP, see chapter 13 “Managing NTP” in the
IBM RISC
System/6000 Scalable POWERparallel Systems: Administration Guide, GC23-3897.
Chapter 5 “The Network Time Protocol” in
RS/6000 SP System Management:
Easy, Lean and Mean, GG24-2563 is also a good source of information.
Chapter 9. User and Services Management
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