AIX Administration You Must Know Questions
1.How do I list information about logical volumes?
Run the following command to display information about the
logical volume #lv1: lslv lv1.
2.How can I clone 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.]
3.How do I replace a disk?
extendvg VolumeGroupName hdisk_new
migratepv hdisk_bad hdisk_new
reducevg -d VolumeGroupName hdisk_bad
4.How do I mirror a logical volume?
mklvcopy LogicalVolumeName Numberofcopies
syncvg VolumeGroupName
5.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
6.How do I get the IP address of my machine?
Type one of the following: ifconfig -a or host
Fully_Qualified_Host_Name. For example, host cyclop.austin.ibm.com.
7.How do I identify the network interfaces on my server?
Either of the following two commands will display the
network interfaces: lsdev -Cc if or ifconfig -a. To get information about one
specific network interface, for eaxample tr0, run the command ifconfig tr0.
8.How do I activate a network interface?
What do you know about TCPDump?TCPdump is a common computer
network debugging tool that runs under the command line. It allowsthe user
to intercept and display TCP/IP and other packets being transmitted or
received over a networkto which the computer is attached. Tcpdump works on
most Unix-like platforms: Linux, Solaris, BSD, MacOS 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.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 avolume group there is a Volume Group D
escriptor 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, importvgthem, and get filesystems
automatically defined.What happens, when you importvg the volume group, the
command goes out and reads the VGDA andfinds out about all the logical volumes
and filesystems that may exist on thevolume group. It then checks for clashes
(name conflicts, etc..) on its own machine and then, populatesits own database
with information about the new volume group andits associated logical volumes.
In cases of file systems, it will go into the /etc/filesystems file and add
thenew filesystem entries that came along with the imported volume group.
9.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 t
ell the system you want to cutout the memory of the old, bad disk
from the RS/6000 AND from the VGDA of the volume group. Yousimply 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 donewith this command WILL affect the VGDA
information on the platter.What is Capacity on Demand?Capacity on Demand
(CoD) encompasses the various capabilities for you to dynamically activate
one ormore resources on your server as your business peaks dictate. You
can activate inactive processors ormemory 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 inactiveresources. Active
processors and active memory units are resources that are available for
use on yourserver when it comes from the manufacturer. Inactive processors
and inactive memory units areresources that are included with your server but
are not available for use until you activate them.
