autoload file | configuration dialog
computer settings | network settings | password policy

 ( idx ) autoload File Explained

The Rembo Wizard's functionality is configured for each host individually with autoload configuration file. When The Rembo Wizard starts, autoload file is searched from Rembo's usual host -> group -> global scope. If there is no autoload file in the host scope, following warning will be shown:

It goes without saying that only systems administrators should see the above message and to continue from this point on is not possible to an end-user. Pressing the Next button will make The Rembo Wizard to do following things:

• Check if there is an autoload file on the group level of this host. If there is it will be copied as the autoload file template for this host.
• In the case that there is no autoload file on the group level, the global level autoload file will be first copied to the group level. All the modifications that will follow in the next dialogs will be registered both in the group level autoload file and in the target host's autoload file.

Important: The autoload file in the host level contains disk partition signature of each system. You cannot therefore blindly copy the autoload file from one host's scope to an other without considering the possible differences in the partition tables.

If The Rembo Wizard detects a mismatch between the target system's partition table and the partition table signature registered in the autoload file, an alert is given as illustrated on the left.

If you have copied the autoload file intentionally as it is - for the needs of cloning, for example - you would anser No here. You would then have to select Unattended or AutoRepair installation options to force the copied partition table to take effect. This would obviously lead to the total loss of all information on the first system disk.

If you answer Yes the target system's actual partition table will become the partition table signature in the autoload file. The change is still not immediate but you have to time for reflection as explains the pop-up message on the right.

The Rembo Toolkit allows the autoload file to be located in the user scope. The Rembo Wizard uses this feature but only in a temporary manner. During the configuration dialog, some configuration settings are stored in the user scope. When the configuration dialog closes, all the temporary settings in the user level autoload file are removed. If you cut out the power, for example, while the configuration dialog is open, some settings may remain active in the user level autoload file. Always leave the configuration dialog before cutting the power off.

 ( idx ) Configuration Dialog

Configuration dialog is started automatically if no autoload file exists for the host. It can be started any time by the system administrator from The Rembo Wizard main menu. A password protected administrator's menu opens, containing a button for the client configuration.

A configuration dialog box opens with following contents.

Information about the target system is listed on the top of the dialog. The information can be less complete than illustrated.

The Rembo Wizard comes with a template file called rembo-names. It is intended to contain your organization's nomenclature for the Machine Types and Operating System Types. You can view the rembo-names file with this button.

Type here in three capital letters the type of the machine according to your organization's nomenclature. If this a new machine type, invent a new letter combination (and do not forget to update the rembo-names file). If available, manufacturer's information is illustrated on the right.

Type here in three capital letters the type of the operating system according as explained in the distribution's  rembo-names file. You do not want to make up any new operating system types at this point.

The system partition images stored in the Rembo Server's file system can be compressed to a high degree. This operation - which saves a considerable amount of disk space - is a CPU intensive and time consuming operation that occurs on the server side. As a rule we could say that for end-users who take images of their systems for backup purposes themselves, do not use image compression for faster operation. For servers, control system machines and such use compressions.

When The Rembo Wizard starts, it checks the following flags for automated operations.

Unattended installation does not require keyboard, screen or mouse. Even your presence is not required! When this flag is on, system's first disk get partitioned according to the partition table signature stored in the autoload-file. All data on the system partitions will be lost. The boot partition, the system partition and the swap partition (for Linux) will be formatted. Possible data partitions will not be formatted but depending of the operating system they may become unusable. The first base operating system image found in the scope order host -> group -> global will be installed on the first partition. Typical usage is when installing a cluster of servers or when distributing a new version of installation on a group of control system machines.

When AutoRepair flag is on, the system's first disk partition table is inspected against the partition table signature stored in the autoload-file. If the signature is different than what is found from the hard disk, the The Rembo Wizard will switch to the Unattended installation, as explained above. Typical usage is with the control system machines: When such a machine's hard disk breaks down, maintenance service personnel can change the system hard disk with spare. When the system is powered on, it gets automatically regenerated without any intervention from the maintenance personnel.

AutoFix flag is used with the systems that are in the public access areas, for example. They can be programmed to reboot every night and the AutoFix flag instructs The Rembo Wizard to use Rembo's MD5-checksum based selective file regeneration on the system partition. Data partitions and such are not touched and there is no rewriting of the partition tables as with the Unattended installation mode. The synchronization operation is usually somewhat faster than with the Unattended installation.

This is the default if no automatic installation operation is required. Select this option when the user wants to use The Rembo Wizard to make his/her own system level backups.

If you turn this flag off, The Rembo Wizard will stay on the screen and you must push some buttons to get the operating system started.

When Autoboot is on, The Rembo Wizard will try to boot from the system hard disk partition. For Windows systems this is the only possible option. For Linux, Rembo's Linux-boot method is used with the first kernel that is found declared in the /etc/lilo.conf (image is mandatory, root, initrd are used if declared. The operation is not a LILO boot, you do not have to run lilo(8) on the target machine).

When Autoboot is on, The Rembo Wizard will boot the Linux system with a network kernel that was stored on the Rembo Server together with the system's base image (.krn extension). If there is a initial ram disk image attached to the kernel (.initrd extension), it will be passed to the kernel. Typical usage of the network based kernel boot is to make sure that a group of machine all use the same kernel (I/O workstations, control system machines, server clusters and such).

Adjust the time of the progress-bar that gives you an opportinity to stop any of The Rembo Wizard automated procedures.

In public access computers you have probably set up the BIOS so that floppy disk boot is not possible. Select No here as well if this is the case. All others use Yes.

see network settings section if you have need to change the network characteristics for the host.

see computer settings and  password policy section for more information. For most operations these settings do need to be changed.

To save the modifications, press OK. This will also save the current partition table as a partition table signature in the autoload-file (unless there has been a mismatch warning message and you have selected not to store the actual partition table). For the first time configuration you cannot cancel the operation (turn the power off if you are still hesitating).

Confirmation that modifications are stored into the autoload-file of the host scope (and on the group scope, if first time configuration for the group).

 ( idx ) Computer Settings Configuration

Computer settings is a sub-dialog of the configuration dialog. The default settings illustrated above are suitable for most machines with a Linux installation or with an English Windows installation. You can change the default values for your organization by editing the autoload-file on global scope level.

Set the (blank) screen saver delay in minutes. Set 0 (zero) minutes if no screen saver is wanted.

A list of available video modes is given. Select one of the available modes for a preferred video mode. Please note that if the resulting autoload-file is used on a other type of hardware, the word preferred takes its full sense: the given video mode is used only if it available on the system, otherwise first non-text-mode video mode is selected automatically.

A list of available keyboard-map files on the Rembo Toolkit server is given.

If you have a Windows 9x system with a non-English file system, you must select a corresponding code page, otherwise the Rembo OS fails to synchronize your file system.

 ( idx ) Network Settings Configuration

Network settings is a sub-dialog of the configuration dialog. The default settings illustrated above are suitable for a public, 100 Mbit/s, switched Ethernet with 1 Gbit/s backbones. You can change the default values for your organization by editing the autoload-file on global scope level.

The thumb rule is to use Unicast always, when there is no need to generated several machines simultaneously. In public, corporate level networks, use always Unicast protocols. Multicast is useful on private networks. For example, you can regenerate an entire cluster of server machines simultaneously with multicast techniques. Just remember to reserve an empty space of about 1.5 GB at the end of your hard disk for Rembo's disk cache if you select Multicast here.

This option is the same for the Multicast and Unicast protocols. In fact, Rembo uses bunches of 16 packet in the network. This parameter adjust the delay between the bunches. For classical type of Ethernet you may want to select slower speeds than the illustrated 20 Mbit/s. Even with switched 100 Mbit/s Ethernet, do not use Unlimited speed, since this may saturate too much your backbone connections between routers. Use Unlimited speed only on private networks between the target machines and the Rembo Server.

 ( idx ) Configuring Password Policy

With this dialog you can set the password policy to anything from relaxed to paranoid:

This is an equivalent to the BIOS startup password.

Password policy of the different image manipulation operations.

Require password when creating a base image for the system (when there is no images in the host's scope).

Require password when overwriting existing base image of the system (and destroying possible differential images). For most occasions, this should be system administration operation only.

Require password when a base image for the system exists and when the user requires for a new backup for the system.

Require password when for any system restoration operation.

30 May 2002