Error-log analysis is done in service mode when you select the Problem Determination option on theDIAGNOSTIC MODE SELECTION menu.Concurrent ModeUse concurrent mode to run online diagnostics on some of the system resources while the system isrunning normal activity.Because the system is running in normal operation, the following resources cannot be tested in concurrentmode:v SCSI adapters connected to paging devicesv Disk drive used for pagingv Some display adapters and graphics related devicesv Memory (tested during POST)v Processor (tested during POST)The following levels of testing exist in concurrent mode:v The share-test level tests a resource while the resource is being shared by programs running in thenormal operation. This testing is mostly limited to normal commands that test for the presence of adevice or adapter.v The sub-test level tests a portion of a resource while the remaining part of the resource is being usedin normal operation. For example, this test could test one port of a multiport device while the other portsare being used in normal operation.v The full-test level requires the device not be assigned to or used by any other operation. This level oftesting on a disk drive might require the use of the varyoff command. The diagnostics display menus toallow you to vary off the needed resource.Error-log analysis is done in concurrent mode when you select the Problem Determination option on theDIAGNOSTIC MODE SELECTION menu.To run the online diagnostics in concurrent mode, you must be logged in to the AIX operating system andhave proper authority to issue the commands (if help is needed, see the system operator).The diag command loads the diagnostic controller and displays the online diagnostic menus.Maintenance ModeMaintenance mode runs the online diagnostics using the customer’s version of the AIX operating system.This mode requires that all activity on the partition running the AIX operating system be stopped so thatthe online diagnostics have most of the resources available to check. All of the system resources, exceptthe SCSI adapters, memory, processor, and the disk drive used for paging, can be checked.Error log analysis is done in maintenance mode when you select the Problem Determination option onthe DIAGNOSTIC MODE SELECTION menu.Use the shutdown -m command to stop all activity on the AIX operating system and put the AIX operatingsystem into maintenance mode. The diag command is then used to invoke the diagnostic controller so youcan run the diagnostics. After the diagnostic controller is loaded, follow the normal diagnostic instructions.Documentation for the AIX operating system is available from the IBM Eserver pSeries InformationCenter at http://publib16.boulder.ibm.com/pseries/en_US/infocenter/base. Select AIX documentation. TheAIX Documentation CD contains the base set of publications for the operating system, includingsystem-management and end-user documentation.Chapter 6. Using the Online and Standalone Diagnostics 67
