Devices that are connected to the system can be in one of four states.

Devices that are connected to the system can be in one of the following states:

Item

Description

Undefined

The device is unknown to the system.

Defined

Specific information about the device is recorded in the customized database, but it is unavailable to the system.

Available

A defined device is coupled to the operating system, or the defined device is configured.

Stopped

The device is unavailable but remains known by its device driver.

If a tty device and a printer alternately use the same tty connector, both a tty device and a printer are defined on the same parent and port in the device configuration database. Only one of these devices can be configured at a time. When the tty connector is configured, the printer specific setup information is retained until it is configured again. The device is not removed; it is in the defined state. Maintaining a device in defined state retains customized information for a device that is not currently in use, either before it is first made available or while it is temporarily removed from the system.

If a device driver exists for a device, the device can be made available through the device driver.

https://www.ibm.com/docs/en/aix/7.2?topic=nodes-device-states

When a customer calls with a complaint about slow workload performance, it is important to ask for additional details to help pinpoint the source of the issue. This could include details such as which application or process is running slowly, what errors are appearing, how long the issue has been occurring, etc. Having this information will help the administrator to determine the cause of the problem and determine the best course of action. Reference: IBM AIX v7 Administrator Specialty Study Guide (page 5-29).

When a customer reports slow workload performance without additional details, the first step should be to gather more information. This includes asking specific questions about the nature of the workload, when the slowdown occurs, any recent changes to the system, and other pertinent details. This information is crucial for diagnosing the issue accurately and determining the appropriate course of action. Arbitrarily increasing resources like CPU or memory without understanding the root cause may not resolve the issue and can lead to inefficient resource usage. References : IBM AIX Performance Tuning Guide

In the /etc/exports file, the absence of specific permissions next to the /tmp directory implies that it is exported with the default read-write permissions. The /data directory has -ro specified, indicating read-only permissions, and /usr/man has -root=client1 , giving root access to client1 with default read-write permissions. Since no special permissions are indicated for /tmp , it retains the default read-write permissions. References : IBM AIX NFS Documentation

The command used to monitor SAN I/O performance/throughput is iostat -DIRT 60 10. The iostat command is used to monitor I/O performance and throughput on a SAN device. The DIRT (Disk I/O Response Time) flag can be used to display the response time for each I/O request. The last two arguments, 60 and 10, are the interval (in seconds) and the number of iterations respectively. This command will monitor I/O performance/throughput every 60 seconds for 10 iterations.

The lspv command displays information about physical volumes on the system, and it retrieves the information from the Object Data Manager (ODM). The ODM is the database that stores information about the system's hardware configuration, including the PVID of each disk. The Iquerypv command directly queries the disk for its PVID, and is therefore able to display the correct PVID. Reference: IBM AIX v7 Administrator Specialty Study Guide, page 546.

The mount -a command in AIX mounts all file systems that are specified in the /etc/filesystems file and have the attribute mount=true . This ensures that only those file systems that are configured to be automatically mounted are actually mounted when this command is executed. It does not mount all defined file systems, only those marked for automatic mounting. References : IBM AIX Documentation – mount

According to the IBM AIX v7 Administrator Specialty Study Guide, the lsmcode command is used to list the microcode of the system. The -A flag is used to list the microcode level and the active microcode level of the system. This command can be used to confirm the system firmware level which is required to use the IBM Fix Level Recommendation Tool (FLRT).