Chapter 6 Managing Client-Server Support (Overview)

This chapter describes the management of server and client support on a network. Overview information is provided about each system configuration (referred to as a system type) that is supported in the Solaris Operating System. This chapter also includes guidelines for selecting the appropriate system type to meet your needs.

Information in this chapter that pertains only to a specific Solaris release, or was introduced in a specific Solaris release, is labeled accordingly.

This is a list of the overview information in this chapter.

• What's New in Managing Client-Server Support?

• Where to Find Client-Server Tasks

• What Are Servers, Clients, and Appliances?

• What Does Client Support Mean?

• Overview of System Types

• Diskless Client Management Overview

For step-by-step instructions about how to manage diskless client support, see Chapter 7, Managing Diskless Clients (Tasks).

What's New in Managing Client-Server Support?

This section describes new or changed diskless client features in this Solaris release.

Support for Specifying Platform by Using bootadm -p Command

A new -p platform argument has been added to the bootadm command. This option enables you to specify the platform or machine hardware class of a client system in situations where the client platform differs from the server platform, for example when administering diskless clients.

For more information, see the bootadm(1M) man page.

nfs4_domain Keyword Impacts Diskless Client Boot

The set_nfs4_domain script that was delivered in the Solaris 10 OS is no longer used to set the NFSv4 domain. To set the NVSv4 domain, add the new nfs4_domain keyword to the diskless client's sysidcfg file. Note that if the nfs4_domain keyword exists in the sysidcfg file, the first boot of a diskless client sets the domain accordingly.

x86: Diskless Client Changes in the GRUB Boot Environment

An extension has been made to GRUB to enable kernel$, module$, and $ISADIR usage in the menu.lst file.

The bootadm command installs a default boot entry in the menu.lst file that is similar to the following:

kernel$ /platform/i86pc/kernel/$ISADIR/unix
module$ /platform/i86pc/kernel/$ISADIR/unix /platform/i86pc/kernel/$ISADIR/unix -B $ZFS-ROOTFS
module$ /platform/i86pc/$ISADIR/boot_archive

The kernel$ and module$ keywords are identical to the kernel and module commands that are used in the GRUB multiboot implementation. The $ISADIR keyword has the added capability to expand to amd64 on 64-bit capable hardware. If the x86 based system is not 64-bit capable, the $ISADIR keyword is a null value (""). In this instance, the system boots the 32-bit kernel.

These changes do not prevent you from booting of a newer Solaris kernel with an older implementation of GRUB. Nor do the changes prevent you from booting of an older Solaris kernel with a newer implementation of GRUB.

GRUB based booting is not available on SPARC based systems.

The following feature enhancements are part of the new diskless boot scheme:

• The OS server is now capable of serving multiple Solaris releases simultaneously.

  With the new diskless boot scheme, you can perform a pxegrub based network boot , where multiple releases are presented to a client from the GRUB menu.

• Vendor-specific options are now specified in the boot archive.

  In previous releases, client-specific boot properties, typically defined in the bootenv.rc file, were provided by using vendor-specific options for the DHCP setup. The total length of the information that was required frequently exceeded the limit in the DHCP specification.

  With the boot new scheme, this information is part of the boot archive. The PXE/DHCP server is only required to provide the server IP address, the boot file, pxegrub, and possibly a client-specific menu file, through Site Option 150.

x86: Changes to the smdiskless Command

The smdiskless command is used to set up diskless clients. Previously, the smdiskless command set up the root (/) and /usr file systems, then exported these file systems to the client through NFS. To boot the client, you would additionally need to configure the /tftpboot area manually. This manual step is no longer a requirement for setting up a diskless client. The smdiskless command now automatically invokes a script in the /usr/sadm/lib/wbem/config_tftp file, which prepares the /tftpboot area for a PXE boot.

After running the smdiskless command, the /tftpboot/01ethernet-address file is displayed as a link to pxegrub and the /tftpboot/menu.lst.01ethernet-address file, which contains the GRUB menu entry. The ethernet-address in this instance is 01, followed by the Ethernet address of the client network interface. When supplying the Ethernet address of the client network interface, use uppercase letters and do not include colons.

The boot archive of the diskless client is automatically updated during shutdown. If the client's boot archive is out of date when it is shut down, you might need to run the following command from the OS server to update the boot archive:

# bootadm update-archive -f -R /export/root/host-name

where host-name is the host name of the client system.

For more information, see x86: How to Boot the Failsafe Archive to Forcibly Update a Corrupt Boot Archive and the bootadm(1M) man page.

This information applies to both SPARC based and x86 based OS servers that are serving x86 based clients.

For more information on setting up and configuring DHCP, see Chapter 14, Configuring the DHCP Service (Tasks), in System Administration Guide: IP Services.

For more information on how to manage diskless clients in the GRUB boot environment, see Booting an x86 Based System by Using GRUB (Task Map).

Where to Find Client-Server Tasks

Use this table to find step-by-step instructions for setting up server and client support.

What Are Servers, Clients, and Appliances?

Systems on the network can usually be described as one of the system types in this table.

What Does Client Support Mean?

Support can include the following:

• Making a system known to the network (host name and Ethernet address information)

• Providing installation services to remotely boot and install a system

• Providing Solaris OS services and application services to a system with limited disk space or no disk space

Overview of System Types

System types are sometimes defined by how they access the root (/) and /usr file systems, including the swap area. For example, stand-alone systems and server systems mount these file systems from a local disk. Other clients mount the file systems remotely, relying on servers to provide these services. This table lists some of the characteristics of each system type.

Description of a Server

A server system contains the following file systems:

• The root (/) and /usr file systems, plus swap space

• The /export and /export/home file systems, which support client systems and provide home directories for users

• The /opt directory or file system for storing application software

Servers can also contain the following software to support other systems:

• Solaris OS services for diskless systems that are running a different release

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  Note –

  OS client-server configurations, where only one system is running a Solaris release that implements the new boot architecture can result in major incompatibilities. It is therefore recommended that you install or upgrade diskless systems to the same release as the server OS before adding diskless client support. New boot (GRUB) was introduced in the Solaris 10 1/06 release on the x86 platform and in the Solaris 10 10/08 release on the SPARC platform.

  ---

• Clients that use a different platform than the server

• Solaris CD image software and boot software for networked systems to perform remote installations

• JumpStart^TM directory for networked systems to perform custom JumpStart installations

Stand-Alone Systems

A networked stand-alone system can share information with other systems in the network. However, it can continue to function if detached from the network.

A stand-alone system can function autonomously because it has its own hard disk that contains the root (/), /usr, and /export/home file systems and swap space. Thus, the stand-alone system has local access to OS software, executables, virtual memory space, and user-created files.

A stand-alone system requires sufficient disk space to hold its necessary file systems.

A non-networked stand-alone system is a stand-alone system with all the characteristics just listed, except it is not connected to a network.

Diskless Clients

A diskless client has no disk and depends on a server for all its software and storage needs. A diskless client remotely mounts its root (/), /usr, and /home file systems from a server.

A diskless client generates significant network traffic due to its continual need to procure OS software and virtual memory space from across the network. A diskless client cannot operate if it is detached from the network or if its server malfunctions.

For more overview information about diskless clients, see Diskless Client Management Overview.

Description of an Appliance

An appliance, such as the Sun Ray appliance, is an X display device that requires no administration. There is no CPU, fan, disk, and very little memory. An appliance is connected to a Sun display monitor. However, the appliance user's desktop session is run on a server and displayed back to the user.

The X environment is set up automatically for the user and has the following characteristics:

• Relies on a server to access other file systems and software applications

• Provides centralized software administration and resource sharing

• Contains no permanent data, making it a field-replaceable unit (FRU)

Guidelines for Choosing System Types

You can determine which system types are appropriate for your environment by comparing each system type based on the following characteristics:

• Centralized administration

• Can the system be treated as a field-replaceable unit (FRU)?

  This means that a broken system can be quickly replaced with a new system without any lengthy backup and restore operations and no loss of system data.

• Does the system need to be backed up?

  Large costs in terms of time and resources can be associated with backing up a large number of desktop systems.

• Can the system's data be modified from a central server?

• Can the system be installed quickly and easily from a centralized server without handling the client system's hardware?

• Performance

• Does this configuration perform well in desktop usage?

• Does the addition of systems on a network affect the performance of other systems already on the network?

Disk space usage

How much disk space is required to effectively deploy this configuration?

This table describes how each system type scores in terms of each characteristic. A ranking of 1 is most efficient. A ranking of 4 is least efficient.

Diskless Client Management Overview

The following sections and Chapter 7, Managing Diskless Clients (Tasks) describe how to manage diskless client support in the Solaris Operating System (Solaris OS).

A diskless client is a system that depends on an OS server for its operating system, software, and storage. A diskless client mounts its root (/), /usr, and other file systems from its OS server. A diskless client has its own CPU and physical memory and can process data locally. However, a diskless client cannot operate if it is detached from its network or if its OS server malfunctions. A diskless client generates significant network traffic because of its continual need to function across the network.

Starting with the Solaris 9 release, the diskless client commands, smosservice and smdiskless, enable you to manage OS services and diskless client support. In the Solaris 8 release, diskless clients were managed with the Solstice^TM GUI management tools.

OS Server and Diskless Client Support Information

Attempts to add diskless client support using an OS client-server configuration where one system implements the new boot architecture, but the other system does not, can result in major incompatibilities. New boot (GRUB) was implemented on the x86 platform, starting with the Solaris 10 1/06 release and on the SPARC platform, starting with the Solaris 10 10/8 release. Note that adding diskless support on systems that are running a Solaris release that is more recent than that which is running on the OS server is also an unsupported configuration. To avoid potential problems, it is recommended that you install the latest Solaris release before adding diskless client support.

The Solaris releases and architecture types that are supported by the smosservice and smdiskless commands include the following:

• SPARC based servers: Supported in the Solaris 8, Solaris 9, Solaris 10, and Solaris Express releases

• SPARC based clients: Supported in the Solaris 8, Solaris 9, Solaris 10, and Solaris Express releases

• x86 based servers: Supported in the Solaris 9, Solaris 10, and Solaris Express releases

• x86 based clients: Supported in the Solaris 9, Solaris 10, and Solaris Express releases

The following table illustrates the x86 OS client-server configurations that are supported by the smosservice and smdiskless commands. This information applies to the Solaris 9 and the Solaris 10 FCS (3/05) release.

If you are running at least the Solaris 10 1/06 release, or a Solaris Express Community release, it is recommended that you install or upgrade to the same release before adding diskless client support.

The following table describes the SPARC OS client-server configurations that are supported by the smosservice and smdiskless commands. This information applies to the Solaris 8 and Solaris 9 releases, and the Solaris 10 release, up through the Solaris 10 5/08 OS.

If you are running at least the Solaris 10 10/08 release, or a Solaris Express Community release, it is recommended that you install or upgrade to the same release before adding diskless client support.

Diskless Client Management Features

You can use the smosservice and smdiskless commands to add and maintain diskless client support on a network. By using a name service, you can manage system information in a centralized manner so that important system information, such as host names, do not have to be duplicated for every system on the network.

You can perform the following tasks with the smosservice and smdiskless commands:

• Add and modify diskless client support

• Add and remove OS services

• Manage diskless client information in the LDAP, NIS, NIS+, or files name service environment

If you are performing a GRUB based boot on an x86 system, you need to manually set up the DHCP configuration. See x86: How to Prepare for Adding Diskless Clients in a GRUB Based Boot Environment for more information.

You can only use the diskless client commands to set up diskless client booting. You cannot use these commands to set up other services, such as remote installation or profile services. Set up remote installation services by including diskless client specifications in the sysidcfg file. For more information, see Solaris Express Installation Guide: Custom JumpStart and Advanced Installations.

Working With Diskless Client Commands

By writing your own shell scripts and using the commands shown in the following table, you can easily set up and manage your diskless client environment.

You can obtain help on these commands in two ways:

• Use the -h option when you type the command, subcommand, and required options, as shown in the following example.

  % /usr/sadm/bin/smdiskless add -p my-password -u my-user-name -- -h

• View the smdiskless(1M) and smosservice(1M) man pages.

Required RBAC Rights for Diskless Client Management

You can use the smosservice and smdiskless commands as superuser. If you are using role-based access control (RBAC), you can use either a subset of or all of the diskless client commands, according to the RBAC rights to which they are assigned. The following table lists the RBAC rights that are required to use the diskless client commands.

Adding OS Services

A Solaris OS server is a server that provides operating system (OS) services to support diskless client systems. You can add support for an OS server or convert a stand-alone system to an OS server by using the smosservice command.

For each platform group and Solaris release that you want to support, you must add the particular OS service to the OS server. For example, if you want to support SPARC sun-4u systems running the Solaris Express release, you must add the Sun-4u/Solaris Express OS services to the OS server. For each diskless client that you support, you must add the OS service for that client to the OS server. For example, you would need to add OS services to support SPARC sun-4m systems or x86 based systems that run the Solaris 10 or Solaris 9 release, because they are different platform groups.

You must have access to the appropriate Solaris software CD or disk image to add OS services.

Adding OS Services When the OS Server Has Been Patched

When adding OS services to an OS server, you might see an error message stating that you have inconsistent versions of the OS running on the server and the OS that you are trying to add. This error message occurs when the installed version of the OS has packages that were previously patched, and the OS services being added do not have those packages patched, because the patches have been integrated into the packages.

For example, you might have a server that is running the current Solaris release or the Solaris 10 release. You might also have additional OS services loaded on this server, including the Solaris 9 SPARC sun-4m OS services that have been patched. If you try to add the Solaris 8 SPARC sun-4u OS services from a CD-ROM to this server, you could get the following error message:

Error: inconsistent revision, installed package appears to have been 
patched resulting in it being different than the package on your media. 
You will need to backout all patches that patch this package before 
retrying the add OS service option.

Disk Space Requirements for OS Servers

Before you set up your diskless client environment, ensure that you have the required disk space available for each diskless client directory.

In previous Solaris releases, you were prompted about diskless client support during the installation process. Starting with the Solaris 9 release, you must manually allocate an /export file system either during installation or create it after installation. See the following table for specific disk space requirements.

Disk space recommendations can vary, depending on the Solaris release that is installed. For specific information about the disk space recommendations in the current Solaris release, see Disk Space Recommendations for Software Groups in Solaris Express Installation Guide: Planning for Installation and Upgrade.