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Other methods for Controlling Servers


Solaris and AIX offer extensions or variations on the inet daemon approach to controlling server processes. Under Solaris, inetd may be placed under the control of the Service Access Facility[1]. However, as the following quote from the Solaris startup scripts shows, the more usual approach is to run inetd in “standalone” mode:

# Run inetd in " standalone " mode (-s flag) 
# so that it doesn't have
# to submit to the will of SAF. 
# Why did we ever let them change inetd?
./rc2.d/S72inetsvc:/usr/sbin/inetd –s


Under AIX, groups of daemon processes may be organized under the system resource controller (SRC). A suite of commands (startsrc, stopsrc, and lssrc are the most important examples) enable the administrator to work with groups of daemons. The services associated with TCP/IP are started and stopped with these commands:

host# startsrc –g tcpip
host# stopsrc –g tcpip

The TCP/IP portion of the SRC may be configured using:
host# smit configtcp
However, the inetd functions under AIX just as described above.

Master Maps

When the automounter first starts, it reads the file /etc/auto_master to determine where to find the direct and indirect map files. The auto_master file is known as the master map. It consists of lines whose format is as follows:

directory map

Here, directory is the name of the directory that corresponds to the indirect map. For a direct map, this entry is /–. The map is the name of the map file in the /etc directory corresponding to the directory given in the first column. The following example shows a master map file for the direct and indirect maps given earlier in this section:
# Master map for automounter
/home auto_home
/- auto_direct

Other entries can also be made in the master map. For example, to share a common directory for mail between a number of clients and a mail server, you would enter the following definition:
/- /etc/auto_mail

This creates a share called auto_mail that makes mail on a single server accessible to all client machines upon request. The automounter permits two kinds of shares that can be defined by direct and indirect maps: a direct map is a set of arbitrary mount points that are listed together, while an indirect map mounts everything under a specific directory. For example, auto_home mounts user directories and all subdirectories underneath them. If an automounted share is available on the server, then you should see its details being displayed in the /etc/mnttab file:
burbank:/var/mail /var/mail nfs nosuid,dev=2bc0012 951071258

Continuing with the example of auto_mail, as defined in the master map, a file named /etc/auto_mail would have to contain the following entry:
# cat /etc/auto_mail
/var/mail burbank:/var/mail

This ensures that the burbank server knows where to find the /var/mail directory physically, and that automount can mount the shared volume at will. Sometimes, the network load caused by mounting and unmounting home directories can lead to an increase in I/O load, and reduce the effective bandwidth of a network. For this reason, only volumes that need to be shared should be shared. Alternatively, the timeout parameter for automount can be modified to extend its latency for mounting and unmounting directories.
[1] Service Access Facility: The Service Access Facility is a Solaris mechanism for controlling access to server processes.