Go to Top

Blog Archives

System Dumps

Dump – Core AIX generates a system dump when a severe error occurs. A system dump creates a picture of the system’s memory contents. If the AIX kernel crashes kernel data is written to the primary dump device. After a kernel crash AIX must be rebooted. During the next boot, the dump is copied into a dump directory (default is /var/adm/ras). The dump file name is vmcore.x (x indicates a number, …Read More

Error Reporting & Diagnosis

Errpt – Diag – Alog – Syslogd ERROR LOGGING: The errdemon is started during system initialization and continuously monitors the special file /dev/error for new entries sent by either the kernel or by applications. The label of each new entry is checked against the contents of the Error Record Template Repository, and if a match is found, additional information about the system environment or hardware status is added. A memory buffer …Read More


FIRMWARE:ADAPTER/SYSTEM FIRMWARE: lsmcode -A                   displays microcode (same as firmware) level information for all supported devices (Firmware: Software that has been written onto read-only memory (ROM)) lsmcode -c                   shows firmware level for system, processor invscout: it helps to show which firmware (microcode) should be updated: 1. download: http://public.dhe.ibm.com/software/server/firmware/catalog.mic 2. copy on the server to:  /var/adm/invscout/microcode 3. run: invscout (it will collect …Read More


I/O – AIO, DIO, CIO, RAW Filesystem I/O AIX has special features to enhance the performance of of filesystem I/O for general-purpose file access. These features include read ahead, write behind and I/O buffering. Oracle employs its own I/O optimization and buffering that  in most cases are redundant to those provided by AIX file systems. Oracle uses buffer cache management (data blocks buffered to shared memory), and AIX uses virtual …Read More

Memory Management

Memory hierarchyThe instructions and data that the CPU processes are taken from memory. Memory comes in several layers.Registers – the top layer, it is high speed storage cells (can contain 32-64 bit data)Caches – If data can not be found in registers it will be looked in  the next level, which is cache         L1 cache the fastes an smallest (usually on CPU chip) 32-256 KB         …Read More


ODM (OBJECT DATA MANAGER):It is a database of system and device configuration information integrated into the OS. It is intended for storing system informations: software infos (smit menus and commands, installed filesets…) and device infos (device configurations, tcp/ip configs…) For safety reasons the ODM data is stored in binary format. All ODM commands use the ODMDIR environment variable, that is set in file /etc/environment. The default value of ODMDIR is …Read More

Printer Management

Printing TERMS:print job                A print job is a unit of work to be run on a printer. The system assigns a unique job number to it.queue                    It is where a print job is directed. (It is a stanza in the /etc/qconfig file.)queue device             The stanza in the /etc/qconfig. It specifies the /dev file (printer device) that should be used.qdaemon        …Read More

Volume Group (VG)

VOLUME GROUPWhen you install a system, the first volume group (VG) is created. It is called the rootvg. Your rootvg volume group is a base set of logical volumes required to start the system. It includes paging space, the journal log, boot data, and dump storage, each on its own separate logical volume.A normal VG is limited to 32512 physical partitions. (32 physical volumes, each with 1016 partitions)you can change …Read More

Startup – Shutdown

Startup – Shutdown  mkitab                     adds record to the /etc/inittab file (-i: insert the newline anywher in the inittab file) (without the -i parameter, the line wil be appended to the end of the file) lsitab                     lists record to the /etc/inittab file (lsitab -a –>lists all records of the inittab) chitab                     adds record to the /etc/inittab file uptime        …Read More


System – Kernel The AIX Kernel is the heart (central core) of the operating system. It has complete control over everything that occurs in the system. A kernel can be contrasted with a shell (ksh, bash, csh) which is the outermost part of the operating system and the shell interacts with users via commands. The kernel does not interact directly with the user. It interacts with the shell, with other programs and with the …Read More