IBM AIX_Interview_Questions_Part II

1) What is the port number used by HMC to communicate with the LPAR?

443

2) What is the port number for Telnet, FTP, SSH, RMC and NFS ?

FTP : 21
SSH : 22
Telnet : 23
RMC : 657
NFS: 111

3) What is the command to check NFS Exported file systems?

# showmount -e localhost

4) What is the command to view firewall settings in VIOS ?

$ viosecure firewall -view

5) What is RSCT ?

Reliable, Scalable and Clustering Technology.

6) What is the command to issue hardware failure in AIX to test cluster ?

# halt -q

7) How to re-read the /etc/inittab ?

# telinit q

8) 2 Types of IPAT in Hacmp  ?

* IPAT by Aliases
* IPAT by Replacement.

9) Command to set temp alias?

# ifconfig interface <IP Address> netmask <Netmask> alias

10) Command to set perm alias?

# chdev -l en0 -a alias=<IP Address>,<Netmask>

10) Command to remove alias ?

# ifconfig interface <IP Address> netmask <Netmask> delete

11) Command to list the PCI slots ?

# lsslot -c pci# -a

12) Command to find the parent adapter for a hdisk# ?

# lsdev -Cl hdisk # -F parent

13) Command to list the child devices ?

# lsdev -p pci0

14) Command to take backup of OS ?

# mksysb -vipeX /dev/rmt0

15) Command to view routing table?

# netstat -r

AIX Performance Monitoring Commands

# sar : System Activity Report.
# vmstat : Virtual Memory Monitoring
# iostat : I/O Monitoring.
# lparstat : LPAR Statistics.
# mpstat : LPAR Statistics.
# netstat : Network Traffic Monitoring.
# topas : Global System Monitoring Tool.
# ps auxwww : View process details via CPU and Memory Consumption.
# filemon : Monitor filesystem.
# fileplace : Monitor filesystem.
# entstat : Interface Statistics.
# monhmc : Monitor HMC.

Add a Removable Media Drive

The following procedure uses SMIT to add a CD-ROM drive to your system. Other types of removable media drives are added using different fast paths but all follow the same general procedure. You can also add a removable media drive using Web-based System Manager, the Configuration Manager, or the mkdev command.

1. To add a CD-ROM drive to your system, install the hardware according to the documentation that came with your system.
2. With root authority, type the following SMIT fast path:

   smit makcdr

3. In the next screen, select the drive type from the available list of supported drives.
4. In the next screen, select the parent adapter from the available list.
5. In the next screen, at minimum, select the connection address from the available list. You can also use this screen to select other options. When you are finished, press Enter, and then SMIT adds the new CD-ROM drive.

At this point, the new CD-ROM drive is recognized by your system. To add a read/write optical drive, use the smit makomd fast path. To add a tape drive, use the smit maktpe fast path.

Replace a Failed Physical Volume in a Mirrored Volume Group

The following scenario replaces a failed or failing disk associated with a physical volume within a mirrored volume group. In the instructions, you use the Configuration Manager to configure the new disk (named hdisk10), and then use the replacepv command to replace a physical volume in a mirrored volume group that resides, at least in part, on a failed disk drive (named hdisk02) without losing the physical volume's contents. You do not need to reboot or schedule downtime to complete the following procedure.

1. Select a new disk drive that has a capacity at least as large as the failed disk.
2. With root authority, run the Configuration Manager to configure the new disk. Type the following on the command line:

   cfgmgr -l hdisk10

   The -l flag allows you to configure only the specified device and any "child" devices. Without this flag, the cfgmgr command runs Configuration Manager against the entire system.
3. Replace the physical volume so it can begin using the new disk, using the following command:
   Note:
   If the mirror for the logical volume is stale, the replacepv command does not work correctly.

   replacepv hdisk02 hdisk10

4. When the associated mirrored volume group is the rootvg, you must also run the following commands to clear the failed disk from and add the new disk to the boot image:

   chpv -c hdisk02
   bootlist hdisk10
   bosboot -a

   The chpv -c command clears hdisk02 from the boot image. The bootlist command adds hdisk10 to the list of possible boot devices from which the system can be booted. The bosboot -a command creates a complete boot image on the default boot logical volume.

At this point, the physical volume hdisk02 now maps to the newly configured hdisk10.

Demons that support DLPAR Operations

The following demons have to be in active state to perform DLPAR Operations on the AIX Client.

SubSystems             Groups           
----------                 --------

ctrmc                         rsct 
ctcas                          rsct
IBM.HostRM              rsct_rm
IBM.DRM                  rsct_rm     
IBM.ServiceRM         rsct_rm
IBM.CSMAgentRM      rsct_rm

VIOS Command Related to Networking

$ cfgassist : Menu Driven Utility to Configure TCP/IP Settings.

$ lstcpip -hostname : To view the hostname.

$ lstcpip -adapters : To view Configured Adapters.

$ lstcpip -stored   : To view TCP/IP Configurations.

$ lstcpip -routtable : To view Routing Table.

$ lstcpip -ent4sea  : To view the Physical Adapters to create SEA.

$ lstcpip -vensea : To view the Virtual Adapters to built SEA.

$ lstcpip -ent4ip : To view the interface upon which IP Address can be assigned.

$ lstcpip -sockets : To view all the open sockets

What is T-Factor?

The below post should give an idea about the T-Factor in IBM AIX Physical Volume.

According AIX Redbook, Its noted that a Physical Volume contains 1016 Physical Partitions (PP) and the default size of a Physical Partition is 4MB.

We come across the T-Factor Problem, When we try to extend a Volume Group with the new Physical Volume.

When your Volume Group cannot accommodate for any new PP by the process of extending a Volume Group with the Disk, the command will throw T-Factor Problem.

Solution:

# chvg -t # Vgname /* Command to Change the T-Factor to Increase Max No.of PP's in PV */

How it Works:

With the T-Factor of 2, the Max.No.of PP's in the VG get increase by ( T-Factor * 1016)

So , 2*1016 : 2032 Partitions. So, I am making my Volume Group to be flexible to accommodate  additional 1016 Partitions which is equivalent of 1 Physical Volume. But, Increasing the T-Factor, reduces the number of Physical Volumes that can be added to a Volume Group.