HATS HA History Log records all the details about each failure condition and provides a quick and easy overview of all
the malfunctions that took place.

1. Filing:
   
   HATS HA History Log is filed according to dates. In other words, there is a separate HATS HA History
   Log file for each day. All these files are saved in the /usr/HA/ha_file/ directory.
   
   
2. Automatic Display:
   
   To help you view the HATS HA History Log file more directly, you can select the on for Display Trace
   on the HATS HA main menu. That will keep open a Console window which constantly displays the details
   in the HATS HA History Log file.
   
   

HATS HA can be used with any application on a Sun or Sun compatible machine. In the previous chapters, we have
shown you how to use HATS HA to service NFS and RDBMS jobs. This section gives another example to show you
how to use HATS HA to service Internet jobs. If you provide Internet services to your clients, it may be particularly
helpful.

As an Internet services provider, it is very likely that you are offering multiple services such as e-mail, ftp, www, etc.
HATS HA can service them simultaneously. If HATS HA detects any failure condition in a specific job, it will transfer
that job to the standby machine. You can set up HATS HA to do this in two different ways. The following explanation
assumes that you provide e-mail, ftp, and www on your server.

Note:

To have HATS HA service your Internet services at the same time, all the data for these jobs must be stored on the
shared disk. For example, the entire directory /var/mail of the mail pool for a mail server should be moved from its
original location in a local machine to the shared disk.


1. You can include all these three services in one general job called "internet" for HATS HA. Then you only need to
   set "JOB=internet" in the configuration. However, you need to write one executible file to start and one executible
   file to stop each of the three services. You need altogether six executible files. These six executible files should be
   respectively inserted in the internet_start and internet_stop scripts.
   
   The advantage of including the three services in one general job is that it requires only one ethernet. There are,
   however, two disadvantages. One, it increases the amount of traffic on the ethernet. Two, if one service fails, all
   the three services will be unnecessarily transferred from the active machine to the standby machine.
   
   
2. You can also use three different jobs to provide the three kinds of services. Then you need to set
   "JOB=e-mail,ftp,www" in the configuration. You also need one start script and one stop script for each job,
   for example, ftp_start and www_start.
   
   The disadvantage of this is that you need three ethernets. There are, however, two advantages. One, the traffic
   may not be as heavy. Two, if one service fails, only that service will be transferred from the active machine to
   the standby one while the other two services continue their operation.