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Network Installation Management Guide and Reference
NIM Machines
There are currently three types of machines
that
can be managed in the NIM environment. These are standalone,
diskless, and dataless clients. This section describes the
differences between the machines, the attributes required to define the
machines, and the operations that can be performed on them. The NIM environment
is composed of two basic machine roles: master and client. The
NIM
master manages the installation of the rest of the machines in the NIM
environment. The master is the only machine that can remotely run NIM commands
on the clients. All other machines participating in the NIM environment are
clients to the master, including machines that may also serve resources.
NIM Operations on Client Machines
There are unique operations to initialize
the different client configurations. NIM uses this fact to check that the
operation is a valid operation for a specific client configuration. The
following table shows the operations that can be performed on the different
client configuration types.
NIM
Operation |
Machine Configuration |
Standalone |
Diskless |
Dataless |
bos_inst |
x |
|
|
dkls_init |
|
x |
|
dtls_init |
|
|
x |
diag |
x |
x |
x |
cust |
x |
|
|
fix_query |
x |
|
|
lppchk |
x |
|
|
maint |
x |
|
|
maint_boot |
x |
|
|
reset |
x |
x |
x |
check |
x |
x |
x |
showlog |
x |
x |
x |
reboot |
x |
x |
x |
For more information about NIM operations, see
NIM Operations
.
Defining NIM Clients
Standalone, diskless, and dataless
clients
are defined in the NIM environment using the NIM define operation. The
command line syntax is as follows:
nim -o define -t MachineType -a
Attribute=Value ... MachineName
where the following attributes are required:
-t MachineType |
Specifies the type of machine being defined. Valid values are
standalone, diskless, and dataless. |
-a if=Value ... |
Stores network interface information for a NIM client, and requires
a sequence number when specified. The value for this attribute consists of three
required values and a fourth, optional value:
- Value 1
- Specifies the name of the NIM network to which this interface
connects. If the name of the NIM network is unknown, then the find_net
keyword can be used to match the client's IP address to a defined NIM network.
If the find_net keyword is used, but NIM does not find a matching
network, the optional net_definition attribute should be used to define
the network, as well.
- Value 2
- Specifies the host name associated with this interface.
- Value 3
- Specifies the network adapter hardware address of this interface. A
value of 0 can be specified unless broadcasting is used for network boot
of the client.
- Value 4
- Specifies the logical device name of the network adapter used for
this interface. If this value is not specified, NIM uses a default based on the
type of network interface defined. This field is required when the client is
defined on a heterogeneous network.
This attribute requires a sequence number for NIM to distinguish between multiple network interfaces. Because machines can be
multihomed, NIM allows more than one if attribute per machine.
|
The following attributes are optional:
-a ring_speed=Value |
Specifies the ring speed of the client's token-ring adapter. This
value is required if the client's NIM network is token-ring. This attribute
requires a sequence number for NIM to distinguish between ring speeds for
multiple interfaces on the machine. |
-a cable_type=Value |
Specifies the cable type of the client's ethernet adapter. This
value is required if the client's NIM network is ethernet. This attribute
requires a sequence number for NIM to distinguish between cable types for
multiple interfaces on the machine. |
-a platform=Value |
Specifies the platform of the machine being defined. The default
value is platform=rs6k. Other examples are rspc and chrp.
Run the bootinfo -p command on a running machine to determine its
platform. |
-a netboot_kernel=Value |
Specifies the kernel type of the client. Valid values are up
for uniprocessor machines and mp for multiprocessor machines. The
default
value is netboot_kernel=up. |
-a iplrom_emu=Value |
Specifies the device that contains the IPL ROM emulation software.
IPL ROM emulation is required for machines that do not have bootp-enabled IPL
ROM. |
-a net_definition=Value ... |
Defines a NIM network to be associated with the client being defined. The value for this
attribute consists of two required values and three optional values:
- Value 1 = NetworkType (required)
- Specified values are tok, ent, fddi, and
generic.
- Value 2 = SubnetMask (required)
- Specifies the dotted decimal mask for the network.
- Value 3 = ClientGateway
(optional)
- Specifies the IP address or host name of the default gateway used by
the machine being defined to communicate with the NIM master.
- Value 4 = MasterGateway
(optional)
- Specifies the IP address or host name of the default gateway used by
the NIM master to communicate with clients on other subnets.
- Value 5 = NetworkName
(optional)
- Specifies a name to be given to the NIM definition created for the
network. (Otherwise, a unique default value is assigned.)
When specifying the net_definition
attribute to create or change a machine definition, the find_net keyword
must be specified as the first component of the if attribute for the
machine. The net_definition attribute may also be specified when
defining additional NIM interfaces (if attributes) for machine definitions. |
-a cpuid=Value |
Specifies the CPU ID of the machine being defined. This attribute
can be used for client verification during NIM operations. To display the CPU ID on
a running machine, use the uname -m command. This field is optional and
will be automatically set the first time a client communicates with the NIM
master. |
-a master_port=Value |
Specifies the port number used by the NIM master for socket
communication with the clients. The default master port number is
1058. |
-a
registration_port=Value |
Specifies the port number used by clients to register themselves
with the NIM master. The default registration port number is 1059. |
-a group=Value |
Specifies a machine group to which the client should be added. The
group will be defined if it does not exist. |
-a comments=Value |
Provides comments about the client being defined. |
-a verbose=Value |
Displays information for debugging. Use verbose=5 to show maximum detail. |
Standalone Clients
Standalone NIM clients are clients with
the capability of booting and running from local resources. Standalone clients
mount all file systems from local disks and have a local boot image. Standalone
clients are not dependent upon network servers for operation.
Network Booting a Standalone Client
Although an installed standalone client
is capable of booting from the local disk, it may be necessary to perform a
network boot of the client for certain NIM operations. Clients must boot over the
network in order for NIM to perform a BOS installation (bos_inst) of the
client or to boot into maintenance mode (maint_boot) and diagnostics
(diag). For instructions on booting a client over the network, see Booting a Machine Over the
Network
.
Managing Software on Standalone Clients
The AIX Base Operating System can be
installed directly on standalone clients using the NIM bos_inst
operation. Additional software and updates can be installed and managed on
standalone clients using the NIM cust and maint operations. See
NIM Operations
for more information about these and
other operations.
Diskless and Dataless Clients
Diskless and dataless clients are
machines
that are not capable of booting and running without the assistance of servers
on
a network. As their names imply, diskless clients have no hard disk, and
dataless clients have disks that are unable to hold all the data that may be
required for operation. Diskless machines must mount paging space and all file
systems from remote servers. Dataless machines can only use a local disk for
paging space and the /tmp and /home file systems. Neither
diskless
nor dataless clients have a local boot image, and they must boot from servers
on
the network.
The reasons for defining a machine as diskless
or dataless are:
- Cost savings
No hard disk is required for diskless clients.
Only a small hard disk is needed for dataless clients.
- Manage software configurations on
machines
On diskless and dataless clients, the file
system containing the Base Operating System is mounted from a server. All
client
systems that mount the same file system for BOS run from identical software.
- Manage storage of user data
User data for diskless and dataless clients
are
stored on remote servers. A system administrator can manage storage allocation
and data backups for the client machines by managing the data on the server,
rather than on each machine separately.
Required and Optional Resources for Diskless
and Dataless Clients
The file systems that are mounted by the
diskless and dataless client machines are treated as resources in the NIM
environment. Like other resources, they exist on a server in the NIM
environment, and they are NFS-exported to the clients that use them.
The following resources are managed by NIM to
support diskless and dataless clients:
boot |
Defined as a network boot image for NIM clients. The boot
resource is managed automatically by NIM and is never explicitly allocated or
deallocated by users. |
SPOT |
Defined as a directory structure that contains the AIX run-time
files common to all machines. These files are referred to as the usr parts of
the fileset. The SPOT resource is mounted as the /usr file system
on diskless and dataless clients.
Contains the root parts of filesets.
The
root part of a fileset is the set of files that may be used to configure
the software for a particular machine. These root files are stored in
special directories in the SPOT, and they are used to populate the root
directories of diskless and dataless clients during initialization.
The network boot images used to boot clients
are constructed from software installed in the SPOT.
A SPOT resource is required for both
diskless and dataless clients. |
root |
Defined as a parent directory for client "/" (root)
directories. The client root directory in the root resource is mounted
as the "/" (root) file system on the client.
When the resources for a client are
initialized, the client root directory is populated with configuration
files. These configuration files are copied from the SPOT resource that
has been allocated to the same machine.
A root resource is required for both
diskless and dataless clients. |
dump |
Defined as a parent directory for client dump files. The client dump
file in the dump resource is mounted as the dump device for the
client.
A dump resource is required for both
diskless and dataless clients. |
paging |
Defined as a parent directory for client paging files. The client
paging file in the paging resource is mounted as the paging device for
the client.
A paging resource is required for
diskless clients and optional for dataless clients. |
home |
Defined as a parent directory for client /home directories.
The client directory in the home resource is mounted as the /home
file system on the client.
A home resource is optional for both
diskless and dataless clients. |
shared_home |
Defined as a /home directory shared by clients. All clients
that use a shared_home resource will mount the same directory as the
/home file system.
A shared_home resource is optional for
both diskless and dataless clients. |
tmp |
Defined as a parent directory for client /tmp directories.
The
client directory in the tmp resource is mounted as the /tmp file
system on the client.
A tmp resource is optional for both
diskless and dataless clients. |
resolv_conf |
Contains nameserver IP addresses and a network domain name.
Unlike the other resources used by
diskless/dataless clients, the resolv_conf resource does not remain
mounted by the client. Instead, it is copied to the /etc/resolv.conf
file
in the client's root directory.
A resolv_conf resource is optional for
both diskless and dataless clients. |
Initialization of Diskless and Dataless
Clients
Diskless and dataless clients are not
installed in the same way as standalone machines. Instead, they are
initialized.
Initialization of diskless and dataless clients involves several phases of
operation:
Resource Allocation |
The resources required to support a diskless/dataless client must be
allocated to the client before or during the initialization operation.
If the resource is a parent directory of
client
directories, the allocation will create an empty subdirectory for the client.
The client subdirectory is then NFS-exported to the client. The client
subdirectories are not populated until the initialization is actually
performed. |
Client Initialization |
The dkls_init and dtls_init operations are used in NIM
to initialize the resources for client use.
Among the operations performed during client
initialization are the following:
- The boot image is made available to the
client for performing a network boot.
- The root files, which are used for
machine-specific customization, are copied into the client's subdirectory in
the
root resource. The files that are copied into the client root
directories
come from the SPOT resource that has been allocated to the client.
- The
/tftpboot/Client.info
file is created on the boot server (which is the SPOT server). This file
contains information that will be needed by the client during the start-up
configuration processing to successfully configure as a diskless or dataless
client.
The following are some of the variables
defined
in the Client.info file:
export NIM_CONFIGURATION=diskless
export RC_CONFIG=rc.dd_boot
export ROOT=Host:Client_Root_Directory
export DUMP=Host:Client_Dump_Directory
export SPOT=Host:SPOT_Location
The paging location is set in the client's root directory in the
/etc/swapspaces file.
|
Network Boot of the Client |
The client machine is booted over the network using standard
bootp procedures for the machine type. The client obtains the boot image
and begins running a mini-kernel in a file system in RAM.
The client tftp's the
Client.info
file from the /tftpboot directory on the SPOT server. The
information in the Client.info file is used to properly configure
the client as a diskless or dataless machine.
The remote file systems are mounted from the
resource servers.
If the client is a dataless client, and no
paging, tmp, home, or shared_home resource is
allocated, then the client will create the missing file system on the local
hard disk. |
Managing Software on Diskless and Dataless
Clients
The /usr and root file
systems of diskless and dataless clients are resources that have been mounted
from a server. Therefore, in order to install or deinstall software on a
diskless/dataless client, the processing must actually occur on the resources
that the clients use.
The SPOT contains the directory
structure for an installed /usr file system. It also contains
subdirectories for the "root" parts of installed filesets. Since the
SPOT
contains both usr and root files, software maintenance must be
performed on the SPOT in order to update the software that is running on
the clients. Such actions must be performed using the NIM cust and
maint operations. See NIM Operations
for more information about the
cust and maint operations.
If the SPOT is currently allocated for
client use, NIM will prevent software customization operations from being
performed on it. This is to safeguard the SPOT from changes that may
adversely affect running client machines. However, this restriction can be
overridden by specifying the force option when performing the operation.
When NIM is used to install software in a
SPOT, the following operations are performed to manage the software for
diskless and dataless clients:
- The /usr files are installed in
the
SPOT. These files are automatically seen by all the clients that mount
the SPOT as their /usr file systems.
- The root files are installed in special
subdirectories in the SPOT.
- After all the filesets have been installed in
the SPOT, the root files are copied to the root
directories
of any diskless or dataless clients that have been initialized with the
SPOT.
When NIM is used to deinstall software in a
SPOT, the following operations are performed to manage the software for
diskless and dataless clients:
- The /usr files are removed from
the
SPOT. This automatically "removes" the files from the client systems as
well.
- The root files of the software are
removed from the client root directories.
NIM also provides a sync_roots
operation
to perform consistency verification and correction to ensure the client
root directories match the root parts stored in the SPOT.
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