ugh.book

198 Programming

NAME

nanny - A server to run all servers

SYNOPSIS

/etc/nanny [switch [argument]] [...switch [argument]]

DESCRIPTION

Most systems have a number of servers providing utilities for

the system and its users. These servers, unfortunately, tend to

go west on occasion and leave the system and/or its users

without a given service. Nanny was created and implemented

to oversee (babysit) these servers in the hopes of preventing the

loss of essential services that the servers are providing without

constant intervention from a system manager or operator.

In addition, most servers provide logging data as their output.

This data has the bothersome attribute of using up the disk

space where it is being stored. On the other hand, the logging

data is essential for tracing events and should be retained when

possible. Nanny deals with this overflow by being a go-

between and periodically redirecting the logging data to new

files. In this way, the logging data is partitioned such that old

logs are removable without disturbing the newer data.

Finally, nanny provides several control functions that allow an

operator or system manager to manipulate nanny and the

servers it oversees on the fly.

SWITCHES

....

BUGS

A server cannot do a detaching fork from nanny. This causes

nanny to think that the server is dead and start another one time

and time again.

As of this time, nanny can not tolerate errors in the

configuration file. Thus, bad file names or files that are not

really configuration files will make nanny die.

Not all switches are implemented.

Nanny relies very heavily on the networking facilities provided

by the system to communicate between processes. If the

network code produces errors, nanny can not tolerate the errors

and will either wedge or loop.