TMF Planning and Configuration Guide (G06.26+)

Doing an Initial Configuration

HP NonStop TMF Planning and Configuration Guide—522416-005

2-2

Adding the Master Audit Trail (MAT)

You use the ADD AUDITTRAIL command to add the master audit trail (MAT) to your

system.

When configuring a typical TMF environment, the only MAT parameter values you

must configure are the audit-trail file size and the number of audit trail files on the

active-audit volume.

Audit-Trail File Size

You use the FILESIZE parameter of the ADD AUDITTRAIL or ALTER AUDITTRAIL

commands to specify the desired audit-trail file size.

The minimum recommended file size is 300 megabytes.

The maximum recommended file size is the average daily audit-generation rate (this

file size results in approximately one audit dump each day).

Your service provider can help you estimate the anticipated audit generation rate. This

rate is highly variable depending on your application and data, and you might need to

experiment with your TMF configuration to find the optimal rollover frequency for your

application. If you are running applications that have already been functional under a

previous release of TMF, the audit generation rates from that environment will be close

enough to use in planning for the D46 TMF environment.

If you are designing new applications, however, you should consult your systems

analysts and application programmers to estimate the following:

1. How many disk writes, typically, would be involved in each transaction

2. How many bytes of data, typically, would be transferred in each disk write

3. How many transactions, typically, would occur during each business hour

Table 2-1 summarizes these guidelines.

To change the audit-trail file size after TMF is started, issue an ALTER AUDITTRAIL

command containing the desired FILESIZE parameter.

If you err in choosing the most appropriate audit-trail file size, it would be better from

an operational standpoint to specify a file size that is too large rather than too small. In

Table 2-1. Audit-Trail File Size

File Size Value

Maximum 95% of the capacity of one tape.

Minimum 5 megabytes.

Recommended If the daily audit generation rate is expected to be greater than the

maximum file size, use the maximum file size; otherwise, use the daily

audit generation rate as the file size.