aix -Q & A

AIX Interview Questions and Answers

What is mean by AIX?
AIX means advanced interactive executive. IBM has invented AIX which is nothing but the advanced UNIX.


Kernel
How would I know if I am running a 32-bit kernel or 64-bit kernel?
To display if the kernel is 32-bit enabled or 64-bit enabled, type:
bootinfo -K

How do I know if I am running a uniprocessor kernel or a multiprocessor kernel?
/unix is a symbolic link to the booted kernel. To find out what kernel mode is running, enter ls -l /unix and see what file /unix it links to. The following are the three possible outputs from the ls -l /unix command and their corresponding kernels:
/unix -> /usr/lib/boot/unix_up # 32 bit uniprocessor kernel
/unix -> /usr/lib/boot/unix_mp # 32 bit multiprocessor kernel
/unix -> /usr/lib/boot/unix_64 # 64 bit multiprocessor kernel

Note:
AIX 5L Version 5.3 does not support a uniprocessor kernel.
How can I change from one kernel mode to another?
During the installation process, one of the kernels, appropriate for the AIX version and the hardware in operation, is enabled by default. Let us use the method from the previous question and assume the 32-bit kernel is enabled. Let us also assume that you want to boot it up in the 64-bit kernel mode. This can be done by executing the following commands in sequence:
ln -sf /usr/lib/boot/unix_64 /unix
ln -sf /usr/lib/boot/unix_64 /usr/lib/boot/unix

bosboot -ad /dev/hdiskxx
shutdown -r

The /dev/hdiskxx directory is where the boot logical volume /dev/hd5 is located. To find out what xx is in hdiskxx, run the following command:
lslv -m hd5


Note:
In AIX 5.2, the 32-bit kernel is installed by default. In AIX 5.3, the 64-bit kernel is installed on 64-bit hardware and the 32-bit kernel is installed on 32-bit hardware by default.
Hardware
How would I know if my machine is capable of running AIX 5L Version 5.3?
AIX 5L Version 5.3 runs on all currently supported CHRP (Common Hardware Reference Platform)-based POWER hardware.
How would I know if my machine is CHRP-based?
Run the prtconf command. If it's a CHRP machine, the string chrp appears on the Model Architecture line.
How would I know if my System p machine (hardware) is 32-bit or 64-bit?
To display if the hardware is 32-bit or 64-bit, type:
bootinfo -y

How much real memory does my machine have?
To display real memory in kilobytes (KB), type one of the following:
bootinfo -r

lsattr -El sys0 -a realmem

Can my machine run the 64-bit kernel?
64-bit hardware is required to run the 64-bit kernel.
What are the values of attributes for devices in my system?
To list the current values of the attributes for the tape device, rmt0, type:
lsattr -l rmt0 -E

To list the default values of the attributes for the tape device, rmt0, type:
lsattr -l rmt0 -D

To list the possible values of the login attribute for the TTY device, tty0, type:
lsattr -l tty0 -a login -R

To display system level attributes, type:
lsattr -E -l sys0

How many processors does my system have?
To display the number of processors on your system, type:
lscfg | grep proc

How many hard disks does my system have and which ones are in use?
To display the number of hard disks on your system, type:
lspv

How do I list information about a specific physical volume?
To find details about hdisk1, for example, run the following command:
lspv hdisk1


How do I get a detailed configuration of my system?
Type the following:
lscfg

The following options provide specific information:
-p Displays platform-specific device information. The flag is applicable to AIX 4.2.1 or later.
-v Displays the VPD (Vital Product Database) found in the customized VPD object class.
For example, to display details about the tape drive, rmt0, type:
lscfg -vl rmt0

You can obtain very similar information by running the prtconf command.
How do I find out the chip type, system name, node name, model number, and so forth?
The uname command provides details about your system.
uname -p Displays the chip type of the system. For example, PowerPC.
uname -r Displays the release number of the operating system.
uname -s Displays the system name. For example, AIX.
uname -n Displays the name of the node.
uname -a Displays the system name, nodename, version, machine ID.
uname -M Displays the system model name. For example, IBM, 9114-275.
uname -v Displays the operating system version.
uname -m Displays the machine ID number of the hardware running the system.
uname -u Displays the system ID number.
AIX
What version, release, and maintenance level of AIX is running on my system?
Type one of the following:
oslevel -r

lslpp -h bos.rte

How can I determine which fileset updates are missing from a particular AIX level?
To determine which fileset updates are missing from 5300-04, for example, run the following command:
oslevel -rl 5300-04

What SP (Service Pack) is installed on my system?
To see which SP is currently installed on the system, run the oslevel -s command. Sample output for an AIX 5L Version 5.3 system, with TL4, and SP2 installed would be:
oslevel –s
5300-04-02


Is a CSP (Concluding Service Pack) installed on my system?
To see if a CSP is currently installed on the system, run the oslevel -s command. Sample output for an AIX 5L Version 5.3 system, with TL3, and CSP installed would be:
oslevel –s
5300-03-CSP


How do I create a file system?
The following command will create, within volume group testvg, a jfs file system of 10MB with mounting point /fs1:
crfs -v jfs -g testvg -a size=10M -m /fs1


The following command will create, within volume group testvg, a jfs2 file system of 10MB with mounting point /fs2 and having read only permissions:
crfs -v jfs2 -g testvg -a size=10M -p ro -m /fs2


How do I change the size of a file system?
To increase the /usr file system size by 1000000 512-byte blocks, type:
chfs -a size=+1000000 /usr

Note:
In AIX 5.3, the size of a JFS2 file system can be shrunk as well.
How do I mount a CD?
Type the following:
mount -V cdrfs -o ro /dev/cd0 /cdrom

How do I mount a file system?
The following command will mount file system /dev/fslv02 on the /test directory:
mount /dev/fslv02 /test

How do I mount all default file systems (all standard file systems in the /etc/filesystems file marked by the mount=true attribute)?
The following command will mount all such file systems:
mount {-a|all}

How do I unmount a file system?
Type the following command to unmount /test file system:
umount /test

How do I display mounted file systems?
Type the following command to display information about all currently mounted file systems:
mount

How do I remove a file system?
Type the following command to remove the /test file system:
rmfs /test

How can I defragment a file system?
The defragfs command can be used to improve or report the status of contiguous space within a file system. For example, to defragment the file system /home, use the following command:
defragfs /home

Which fileset contains a particular binary?
To show bos.acct contains /usr/bin/vmstat, type:
lslpp -w /usr/bin/vmstat

Or to show bos.perf.tools contains /usr/bin/svmon, type:
which_fileset svmon

How do I display information about installed filesets on my system?
Type the following:
lslpp -l


How do I determine if all filesets of maintenance levels are installed on my system?
Type the following:
instfix -i | grep ML

How do I determine if a fix is installed on my system?
To determine if IY24043 is installed, type:
instfix -ik IY24043

How do I install an individual fix by APAR?
To install APAR IY73748 from /dev/cd0, for example, enter the command:
instfix -k IY73748 -d /dev/cd0


How do I verify if filesets have required prerequisites and are completely installed?
To show which filesets need to be installed or corrected, type:
lppchk -v

How do I get a dump of the header of the loader section and the symbol entries in symbolic representation?
Type the following:
dump -Htv

How do I determine the amount of paging space allocated and in use?
Type the following:
lsps -a

How do I increase a paging space?
You can use the chps -s command to dynamically increase the size of a paging space. For example, if you want to increase the size of hd6 with 3 logical partitions, you issue the following command:
chps -s 3 hd6


How do I reduce a paging space?
You can use the chps -d command to dynamically reduce the size of a paging space. For example, if you want to decrease the size of hd6 with four logical partitions, you issue the following command:
chps -d 4 hd6


How would I know if my system is capable of using Simultaneous Multi-threading (SMT)?
Your system is capable of SMT if it's a POWER5-based system running AIX 5L Version 5.3.
How would I know if SMT is enabled for my system?
If you run the smtctl command without any options, it tells you if it's enabled or not.
Is SMT supported for the 32-bit kernel?
Yes, SMT is supported for both 32-bit and 64-bit kernel.
How do I enable or disable SMT?
You can enable or disable SMT by running the smtctl command. The following is the syntax:
smtctl [ -m off | on [ -w boot | now]]

The following options are available:
-m off Sets SMT mode to disabled.
-m on Sets SMT mode to enabled.
-w boot Makes the SMT mode change effective on next and subsequent reboots if you run the bosboot command before the next system reboot.
-w now Makes the SMT mode change immediately but will not persist across reboot.
If neither the -w boot or the -w now options are specified, then the mode change is made immediately. It persists across subsequent reboots if you run the bosboot command before the next system reboot.
How do I get partition-specific information and statistics?
The lparstat command provides a report of partition information and utilization statistics. This command also provides a display of Hypervisor information.
Volume groups and logical volumes
How do I know if my volume group is normal, big, or scalable?
Run the lsvg command on the volume group and look at the value for MAX PVs. The value is 32 for normal, 128 for big, and 1024 for scalable volume group.
How to create a volume group?
Use the following command, where spartition_size sets the number of megabytes (MB) in each physical partition where the partition_size is expressed in units of MB from 1 through 1024. (It's 1 through 131072 for AIX 5.3.) The partition_size variable must be equal to a power of 2 (for example: 1, 2, 4, 8). The default value for standard and big volume groups is the lowest value to remain within the limitation of 1016 physical partitions per physical volume. The default value for scalable volume groups is the lowest value to accommodate 2040 physical partitions per physical volume.
mkvg -y name_of_volume_group -s partition_size list_of_hard_disks

How can I change the characteristics of a volume group?
You use the following command to change the characteristics of a volume group:
chvg

How do I create a logical volume?
Type the following:
mklv -y name_of_logical_volume name_of_volume_group number_of_partition

How do I increase the size of a logical volume?
To increase the size of the logical volume represented by the lv05 directory by three logical partitions, for example, type:
extendlv lv05 3


How do I display all logical volumes that are part of a volume group (for example, rootvg)?
You can display all logical volumes that are part of rootvg by typing the following command:
lsvg -l rootvg

How do I list information about logical volumes?
Run the following command to display information about the logical volume lv1:
lslv lv1

How do I remove a logical volume?
You can remove the logical volume lv7 by running the following command:
rmlv lv7

The rmlv command removes only the logical volume, but does not remove other entities, such as file systems or paging spaces that were using the logical volume.
How do I mirror a logical volume?
1. mklvcopy LogicalVolumeName Numberofcopies
2. syncvg VolumeGroupName
How do I remove a copy of a logical volume?
You can use the rmlvcopy command to remove copies of logical partitions of a logical volume. To reduce the number of copies of each logical partition belonging to logical volume testlv, enter:
rmlvcopy testlv 2

Each logical partition in the logical volume now has at most two physical partitions.
Queries about volume groups
To show volume groups in the system, type:
lsvg

To show all the characteristics of rootvg, type:
lsvg rootvg

To show disks used by rootvg, type:
lsvg -p rootvg

How to add a disk to a volume group?
Type the following:
extendvg VolumeGroupName hdisk0 hdisk1 ... hdiskn

How do I find out what the maximum supported logical track group (LTG) size of my hard disk?
You can use the lquerypv command with the -M flag. The output gives the LTG size in KB. For instance, the LTG size for hdisk0 in the following example is 256 KB.
/usr/sbin/lquerypv -M hdisk0
256

You can also run the lspv command on the hard disk and look at the value for MAX REQUEST.
What does syncvg command do?
The syncvg command is used to synchronize stale physical partitions. It accepts names of logical volumes, physical volumes, or volume groups as parameters.
For example, to synchronize the physical partitions located on physical volumes hdisk6 and hdisk7, use:
syncvg -p hdisk4 hdisk5


To synchronize all physical partitions from volume group testvg, use:
syncvg -v testvg


How do I replace a disk?
1. extendvg VolumeGroupName hdisk_new
2. migratepv hdisk_bad hdisk_new
3. reducevg -d VolumeGroupName hdisk_bad
How can I clone (make a copy of ) the rootvg?
You can run the alt_disk_copy command to copy the current rootvg to an alternate disk. The following example shows how to clone the rootvg to hdisk1.
alt_disk_copy -d hdisk1

Network
How can I display or set values for network parameters?
The no command sets or displays current or next boot values for network tuning parameters.
How do I get the IP address of my machine?
Type one of the following:
ifconfig -a

host Fully_Qualified_Host_Name

For example, type host cyclop.austin.ibm.com.
How do I identify the network interfaces on my server?
Either of the following two commands will display the network interfaces:
lsdev -Cc if

ifconfig -a

To get information about one specific network interface, for example, tr0, run the command:
ifconfig tr0

How do I activate a network interface?
To activate the network interface tr0, run the command:
ifconfig tr0 up

How do I deactivate a network interface?
For example, to deactivate the network interface tr0, run the command:
ifconfig tr0 down
AIX Interview Questions and Answers
1.Can you explain the steps to Mirroring rootvg in your environment?
Mirroring "rootvg" protects the operating system from a disk failure. Mirroring "rootvg" requires a couple extra steps compared to other volume groups. The mirrored rootvg disk must be bootable *and* in the bootlist. Otherwise, if the primary disk fails, you'll continue to run, but you won't be able to reboot.
In brief, the procedure to mirror rootvg on hdisk0 to hdisk1 is
1. Add hdisk1 to rootvg: extendvg rootvg hdisk1
2. Mirror rootvg to hdisk1: mirrorvg rootvg hdisk1 (or smitty mirrorvg)
3. Create boot images on hdisk1: bosboot -ad /dev/hdisk1
4. Add hdisk1 to the bootlist:bootlist -m normal hdisk0 hdisk1
5. Reboot to disable quorum checking on rootvg. The mirrorvg turns off quorum by default, but the system needs to be rebooted for it to take effect.
2.What is VPN and how it works?
A VPN is a private network that uses a public network (usually the Internet) to connect remote sites or users together. Instead of using a dedicated, real-world connection such as leased line, a VPN uses "virtual" connections routed rough the Internet from the company's private network to the remote site or employee.
What is daemon?
A daemon (pronounced DEE-muhn) is a program that runs continuously and exists for the purpose of handling periodic service requests that a computer system expects to receive. The daemon program forwards the requests to other programs (or processes) as appropriate. Each server of pages on the Web has an HTTPD or Hypertext Transfer Protocol daemon that continually waits for requests to come in from Web clients and their users.
There are several daemon in AIX environment, such as, sshd, inetd, and so on.
3.Can you describe SAN in your won word?
A storage area network (SAN) is a high-speed special-purpose network (or subnetwork) that interconnects different kinds of data storage devices with associated data servers on behalf of a larger network of users. Typically, a storage area network is part of the overall network of computing resources for an enterprise. A storage area network is usually clustered in close proximity to other computing resources such as IBM Power5 boxes but may also extend to remote locations for backup and archival storage, using wide area network carrier technologies such as ATM or SONET .
A storage area network can use existing communication technology such as IBM's optical fiber ESCON or it may use the newer Fibre Channel technology. Some SAN system integrators liken it to the common storage bus (flow of data) in a personal computer that is shared by different kinds of storage devices such as a hard disk or a CD-ROM player.
SANs support disk mirroring, backup and restore, archival and retrieval of archived data, data migration from one storage device to another, and the sharing of data among different servers in a network. SANs can incorporate subnetworks with network-attached storage (NAS) systems.
4.So you mention NAS, but What is NAS?
Network-attached storage (NAS) is hard disk storage that is set up with its own network address rather than being attached to the department computer that is serving applications to a network's workstation users. By removing storage access and its management from the department server, both application programming and files can be served faster because they are not competing for the same processor resources. The network-attached storage device is attached to a local area network (typically, an Ethernet network) and assigned an IP address. File requests are mapped by the main server to the NAS file server.
Network-attached storage consists of hard disk storage, including multi-disk RAID systems, and software for configuring and mapping file locations to the network-attached device. Network-attached storage can be a step toward and included as part of a more sophisticated storage system known as a storage area network (SAN).
NAS software can usually handle a number of network protocols, including Microsoft's Internetwork Packet Exchange and NetBEUI, Novell's Netware Internetwork Packet Exchange, and Sun Microsystems' Network File System. Configuration, including the setting of user access priorities, is usually possible using a Web browser.
5.What is SMTP and how it works?
SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-mail. However, since it is limited in its ability to queue messages at the receiving end, it is usually used with one of two other protocols, POP3 or IMAP, that let the user save messages in a server mailbox and download them periodically from the server. In other words, users typically use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving e-mail. On Unix-based systems, sendmail is the most widely-used SMTP server for e-mail. A commercial package, Sendmail, includes a POP3 server. Microsoft Exchange includes an SMTP server and can also be set up to include POP3 support.
SMTP usually is implemented to operate over Internet port 25.
6.Do you have any idea about NAT?
Short for Network Address Translation, an Internet standard that enables a local-area network (LAN) to use one set of IP addresses for internal traffic and a second set of addresses for external traffic. A NAT box located where the LAN meets the Internet makes all necessary IP address translations.
NAT serves three main purposes:
• Provides a type of firewall by hiding internal IP addresses
• Enables a company to use more internal IP addresses. Since they're used internally only, there's no possibility of conflict with IP addresses used by other companies and organizations.
• Allows a company to combine multiple ISDN connections into a single Internet connection.
7.Explain DHCP and its uses to an environment?
Short for Dynamic Host Configuration Protocol, a protocol for assigning dynamic IP addresses to devices on a network. With dynamic addressing, a device can have a different IP address every time it connects to the network. In some systems, the device's IP address can even change while it is still connected. DHCP also supports a mix of static and dynamic IP addresses.
Dynamic addressing simplifies network administration because the software keeps track of IP addresses rather than requiring an administrator to manage the task. This means that a new computer can be added to a network without the hassle of manually assigning it a unique IP address. Many ISPs use dynamic IP addressing for dial-up users.
8.What does SNMP stands for?
Short for Simple Network Management Protocol, a set of protocols for managing complex networks. SNMP works by sending messages, called Protocol Data Units, to different parts of a network. SNMP-compliant devices, called Agents, store data about themselves in Management Information Bases and return this data to the SNMP requesters.
9.What do you know about TCPDump?
TCPdump is a common computer network debugging tool that runs under the command line. It allows the user to intercept and display TCP/IP and other packets being transmitted or received over a network to which the computer is attached. Tcpdump works on most Unix-like platforms: Linux, Solaris, BSD, Mac OS X, HP-UX and AIX among others. On Windows, WinDump can be used; it's a port of tcpdump to Windows.
You must have a root or super user authority to use TCPdumps in UNIX like envrionment.
10.How do I remove a volume group with no disks?
This is a very common question about AIX LVM and I knew that you will ask me this one. Within a volume group there is a Volume Group Descriptor Area (VGDA) which is kinda a "suitcase" of lvm information. This is what allows you to pick up your drives and take them to another machine, importvg them, and get filesystems automatically defined.
What happens, when you importvg the volume group, the command goes out and reads the VGDA and finds out about all the logical volumes and filesystems that may exist on the
volume group. It then checks for clashes (name conflicts, etc..) on its own machine and then, populates its own database with information about the new volume group and
its associated logical volumes. In cases of file systems, it will go into the /etc/filesystems file and add the new filesystem entries that came along with the imported volume group.
The main question I see is "I've taken away the disks, but how do I get rid of the volume group". The question should really say, "How do I get rid of the volume group INFORMATION" since that's all you have on the system. You've got possible entries in
the /etc/filesystems and definitely entries in the ODM. Just do:
exportvg
It does a reverse importvg, except it doesn't go off and read the VGDA. It nukes anything relating to the volume group in the /etc/filesystems and ODM. The only time this won't work is if the system detects that the volume group is varied on. Then, it would be like trying to change tires on a moving car, we won't let you do it!
11.How do you you get rid of a disk that is no longer really in the VG?
In this case, you DON'T want to do an exportvg. What you want to do is tell the system you want to cut out the memory of the old, bad disk from the RS/6000 AND from the VGDA of the volume group. You simply do: reducevg -d -f
or if the hdname can't be found:
reducevg -d -f
Be careful with this command. Unlike the exportvg command, actions done
with this command WILL affect the VGDA information on the platter.
12.What is Capacity on Demand?
Capacity on Demand (CoD) encompasses the various capabilities for you to dynamically activate one or more resources on your server as your business peaks dictate. You can activate inactive processors or memory units that are already installed on your server on a temporary and permanent basis.
Usually, the Capacity on Demand is used for IBM System i5™ and eServer™ i5 and IBM System p5™ and eServer p5 520, 550, 570, 590, and 595 models. Some servers include a number of active and inactive resources. Active processors and active memory units are resources that are available for use on your server when it comes from the manufacturer. Inactive processors and inactive memory units are resources that are included with your server but are not available for use until you activate them.
13.What is Hardware Management Console (HMC)?
The HMC is a server or stand alone machine that provides a graphical user interface tool to manage several Power Systems. The HMC manages system through hypervisor and operating system. From version 7 it is truly web based and you can configure, installs and manage, partitioned, virtualization most of your Power5 and 6 boxes via HMC. There are many tasks you can do with HMC, such as,
• Powering off and on of the partition
• Configure and activate resources to the system
• Creates and stores LPAR profiles and allocated resources to them.
• HMC do the dynamic memory reconfiguration of the partition.
• Setup VIO server and VIO client thru HMC and do micro-partition, create storage
• pool and processor pool with it
• Provide virtual console to the partition
Most of the time we installed dual HMC for redundancy and make sure to achieve more uptime in a wide system
14.Why do I need a Hardware Management Console, anyway?
You need a HMC if you plan to:
– Configure and manage logical partitions and partition profiles (selected models can configure LINUX partitions without a HMC).
– Perform DLPAR (dynamic LPAR) functions.
– Activate and manage Capacity on Demand resources.
You can also use the HMC to:
– Perform service functions
– Manage frames (towers), IOPs and IOAs. * Note that you cannot see below the IOA to the device level.
– Manage system profiles (yes, you can have more than one!)
– Power on and power down. The Service Processor is always hot if there is power to the server.
– Activate and manage Virtualization Engine technologies.
– 5250 emulation so you can get a console up on a i5/OS partition or a virtual terminal window for AIX or LINUX.
15.What is kernel?
The kernel is the essential center of a computer operating system, the core that provides basic services for all other parts of the operating system. A synonym is nucleus. A kernel can be contrasted with a shell, the outermost part of an operating system that interacts with user commands. Kernel and shell are terms used more frequently in UNIX operating systems than in IBM mainframe or Microsoft Windows systems.
Typically, a kernel (or any comparable center of an operating system) includes an interrupt handler that handles all requests or completed I/O operations that compete for the kernel's services, a scheduler that determines which programs share the kernel's processing time in what order, and a supervisor that actually gives use of the computer to each process when it is scheduled. A kernel may also include a manager of the operating system's address spaces in memory or storage, sharing these among all components and other users of the kernel's services. A kernel's services are requested by other parts of the operating system or by application programs through a specified set of program interfaces sometimes known as system calls.
16.What is RMC?
The Resource Monitoring and Control (RMC) subsystem is the scalable backbone of RSCT that provides a generalized framework for managing resources within a single system or a cluster. Its generalized framework is used by cluster management tools to monitor, query, modify, and control cluster resources. RMC provides a single monitoring and management infrastructure for both RSCT peer domains and management domains. RMC can also be used on a single machine, enabling you to monitor and manage the resources of that machine. However, when a group of machines, each running RMC, are clustered together, the RMC framework allows a process on any node to perform an operation on one or more resources on any other node in the domain.
What information is stored in Object Data Manager?
It is a database of system and device configuration information integrated into IBM's AIX operating system. The ODM is unique to AIX compared to other UNIX operating systems.
Example of information stored in the ODM database are:
• Network configuration
• Logical volume management configuration
• Installed software information
• Devices that AIX has drivers for
• Logical devices or software drivers
• Physical hardware device installed
• Menus, screens and commands that SMIT uses
17.Explain a little about Vital Product Data (VPD)?
VPD in AIX and Linux is a collection of configuration and informational data associated with a particular set of hardware or software. VPD refers to a subset of database tables in the Object Data Manager (ODM), Therefore the VPD and ODM terms are sometimes referred to interchangeably.
Vital product data (VPD) stores information such as part numbers, serial numbers, and engineering change levels from the Customized VPD object class or platform specific areas, not all devices contain VPD data.
18.Does HACMP work on different operating systems?
Yes. HACMP is tightly integrated with the AIX 5L operating system and System p servers allowing for a rich set of features which are not available with any other combination of operating system and hardware. HACMP V5 introduces support for the Linux operating system on POWER servers. HACMP for Linux supports a subset of the features available on AIX 5L, however this mutli-platform support provides a common availability infrastructure for your entire enterprise.

19.What applications work with HACMP?
All popular applications work with HACMP including DB2, Oracle, SAP, WebSphere, etc. HACMP provides Smart Assist agents to let you quickly and easily configure HACMP with specific applications. HACMP includes flexible configuration parameters that let you easily set it up for just about any application there is.

20.Does HACMP support dynamic LPAR, CUoD, On/Off CoD, or CBU?
HACMP supports Dynamic Logical Partitioning, Capacity Upgrade on Demand, On/Off Capacity on Demand and Capacity Backup Upgrade.

21.If a server has LPAR capability, can two or more LPARs be configured with unique instances of HACMP running on them without incurring additional license charges?
Yes. HACMP is a server product that has one charge unit: number of processors on which HACMP will be installed or run. Regardless of how many LPARs or instances of AIX 5L that run in the server, you are charged based on the number of active processors in the server that is running HACMP. Note that HACMP configurations containing multiple LPARs within a single server may represent a potential single point-of-failure. To avoid this, it is recommended that the backup for an LPAR be an LPAR on a different server or a standalone server.
22.Does HACMP support non-IBM hardware or operating systems?
Yes. HACMP for AIX 5L supports the hardware and operating systems as specified in the manual where HACMP V5.4 includes support for Red Hat and SUSE Linux.

23.What is nmon tool do?
The nmon tool is designed for AIX and Linux performance specialists to use for monitoring and analyzing performance data, including:
• CPU utilization
• Memory use
• Kernel statistics and run queue information
• Disks I/O rates, transfers, and read/write ratios
• Free space on file systems
• Disk adapters
• Network I/O rates, transfers, and read/write ratios
• Paging space and paging rates
• CPU and AIX specification
• Top processors
• IBM HTTP Web cache
• User-defined disk groups
• Machine details and resources
• Asynchronous I/O — AIX only
• Workload Manager (WLM) — AIX only
• IBM TotalStorage® Enterprise Storage Server® (ESS) disks — AIX only
• Network File System (NFS)
• Dynamic LPAR (DLPAR) changes — only pSeries p5 and OpenPower for either AIX or Linux
Also included is a new tool to generate graphs from the nmon output and create .gif files that can be displayed on a Web site.

24.What is Logical Volume Manager(LVM) means?
The set of operating system commands, library subroutines and other tools that allow you to establish and control logical volume storage is called the Logical Volume Manager (LVM).
25.What is a Logical partition?
A logical partition (LPAR) is the division of a computer’s processors, memory, and hardware resources into multiple environments so that each environment can be operated independently with its own operating system and applications.
26.Explain Network File Systems(NFS)?
The Network File System (NFS) is a distributed file system that allows users to access files and directories of remote servers as if they were local. Suppose,
Server A, that makes its file systems, directories, and other resources available for remote access. Client’s computers, or their processes, that use a server’s resources.
Export the act of making file systems available to remote clients.
Mount the act of a client accessing the file systems that a server exports.
27.What is Network Information Service (NIS)?
NIS was developed to simplify the task of administrating a number of machines over a network. In particular was the requirement to maintain copies of common files (e.g. password, group and host) across different systems.
28.What is software RAID Levels do?
Redundant Arrays of Independent Disks (RAID) is formally defined as a method to store data on any type of disk medium.
29.LDAP
The Light Directory Access Protocol (LDAP) defines a standard method for accessing and updating information in a directory (a database) either locally or remotely in a client-server model.