| Lesson 5 ||The UNIX manual and system administration |
| Objective ||Describe System Administration Issues Involved. |
Describe System Administration Issues Involved
A UNIX administrator must function in a diverse environment. You may start out with a few RS/6000s or a Sun workstation, and become a master of that particular environment. Inevitably, however, someday someone will acquire a UNIX machine from a different company, and then you will start to see the things you have programmed suddenly stop working.
Even if you are fortunate enough to function in a single-vendor environment, you will find it practically impossible to remember the number of commands and options that you need to keep the system running. For these reasons, being able to use the UNIX online manual effectively is one of the key abilities for a UNIX system administrator.
By using man, you can gain helpful information about your UNIX system.
However, the manuals found by using the
man command have several shortcomings:
- They often target a reader who has considerable experience using the particular program you are reading about.
- They are not centrally indexed, which requires you to conduct searches of several different manual entries.
- Each manual page discusses specific commands and daemons, rather than procedures. In other words, you will never find a man page discussing
how to implement a Web server, but you will find entries about daemons and files such as
- As with most things UNIX,
man has an idiosyncratic way of searching for sections of the man page. Despite such issues, you can still navigate your way around these pages by knowing a few commands,
as well as how the program is configured.
Man Page Description
||Use the ipf command to complete the following tasks:
- Work with packet filtering rule sets.
- Disable and enable filtering.
- Reset statistics and resynchronize the in-kernel interface list with the current interface status list.
||Contains the grammar and syntax for creating IP Filter packet filtering rules.
||Provides open source IP Filter licensing information.
||Use the ipfs command to save and restoreNAT information and state table information across reboots.
||Use the ipfstat command to retrieve and display statistics on packet processing.
||Use the ipmon command to open the log device and view logged packets for both packet filtering andNAT.
||Use the ipnat command to complete the following tasks:
- Work withNAT rules.
- Retrieve and displayNAT statistics.
||Contains the grammar and syntax for creatingNAT rules.
||Use the ippool command to create and manage address pools.
||Contains the grammar and syntax for creating IP Filter address pools.
||Displays current filtering parameters of the pfil STREAMS module and the current values of the tunable parameters.
Organization of the manual
The UNIX manual is divided into sections
The most important sections for the administrator are those pertaining to user commands, system administration commands, and configuration files and file formats. Although variations exist among different UNIX systems, overall structure of the manual pages