Backup3G/User Guide/Appendix A - Installing and Configuring

From Documentation

Appendix A — Installing and Configuring

backup3G is installed through the COSmanager configuration menu. This appendix describes how to install and configure backup3G for your environment. COSstacker is an add-on module that provides interface routines for jukebox control under backup3G. For details on installing, configuring, and using COSstacker, see the COSstacker User Guide.

See Installing COSmanager Applications in the COSmanager User Guide for full details of how to install COSmanager applications and modules.

What you need

• the COSmanager framework installed on the target platform
• a backup3G Distribution
• a valid license key
• you must be a COSmanager user with the Manager or Config role

Installing backup3G

1. First, load the distribution tape in a drive on the local host or a network drive.
2. From the Product configuration menu, select COSmanager configuration > COSmanager applications.
3. Select Application > Install.
4. Enter the name of the host to which the tape drive is attached. In Install from, enter the no-rewind device name for the tape drive. Press Accept.
5. You will see a list of the applications on the tape. Choose the row titled ‘backup3G version 3.2’.
6. Enter the name of the directory where you want backup3G to be installed and press Accept.

The install procedure now:

• adds an entry for backup3G 3.2 to the COSmanager applications table
• copies the backup3G files from the tape to the target directory
• creates local directories under $FShome/backup_3.2
• creates symbolic links for the FS backup drivers
• creates the backup3G audit trail directory backlog in the system spool area.

This completes the installation phase.

You should now exit COSmanager before configuring backup3G. When you restart COSmanager, the button bar and COSmanager configuration menu will be rebuilt to include the backup3G options.

Configuring backup3G

The next step is to set up backup3G for your environment, by running some or all of the initial configuration tasks. Some of these configuration tasks supply information that is required by backup3G. Other tasks are optional, and extend the basic information in backup3G to include information about your organization’s procedures and computing environment. You can run or rerun these tasks at any time.

Note We recommend that you review your backup policies and procedures before starting configuration. 
See Planning Your Backup Policies and Procedures.

Running backup3G initial configuration tasks

• • GUI mode: Select Config from the COSmanager button bar.
  • CUI mode: Select Product configuration from the COSmanager main menu.
• Select backup3G configuration > Initial configuration.

COSmanager shows the list of configuration tasks.

• To start configuration, select Perform > All outstanding from the menu bar.

Note In CUI mode, the menu bar is accessible from the function key assigned to the Menu button—usually F8.

For each task you will see a screen offering a number of options, like this:

Figure 40 — Example of an outstanding configuration task

Press Exit to stop the configuration procedure. You can continue the configuration later by selecting Initial configuration from the backup3G configuration menu.

Press Skip to skip to the next outstanding task. Note that some duties later in the configuration require earlier duties to have been run.

Press Accept to execute this task now.

• Work through each task in turn.

The following topics contain some useful information on each task, or a pointer to a detailed description elsewhere in the manual.

Removable Media Drives

This defines a list of available backup drives and drive pools. A backup drive is one that will be used by backup or recovery jobs running on the current host to read or write data. This includes both drives physically connected to this host, and drives accessible via the network.

Any drives that will be used to write to or read media must be defined to backup3G. Auto-loading devices such as tape stackers and jukeboxes should be defined as media locations.

Drives that are accessible but which will not be used for backup and recovery don’t need to be defined to backup3G. For more information see How To Add A New Tape or Disk Drive.

Before you begin

To define a Removable Media Drive you will need to have set up details of:

• all hosts on the network that have a backup drive attached to them. This was probably done when COSmanager was configured. The procedure is described in the COSmanager User Guide, in the chapter Configuring COSmanager. If you need to add a host location now you can do it from this task, through Maintain > Location.
• all media types that will be used for backup. backup3G has a table of standard media types, so you only need to add new or uncommon media types that you use for backup or archive. You can add media types now, through Maintain > Media type. For more information, see Adding a New Media Type.
• all locations from which media are loaded into backup drives, whether short-term (tape stacker, computer-room trolley) or longer-term (jukebox, media library). You can add media and load locations from this task, through Maintain > Location. For more information, see Adding a New Media Location.

Add Media to the Media Library

This task allows you to add details of new media batches to the database. You can also add details of locations where media are stored, and add a new media type.

Media management policies and procedures

This is a good time to review your current media management procedures, to see if you could be using media in a more secure or efficient way. You should consider the following:

• your strategies for routine backup and data recovery (media types, label types, retention periods)
• your media maintenance strategy (media usage types, maintenance procedures)
• where media can be stored and for how long (media locations).

Before you begin

Before you can add backup media, you will need to have set up details of:

• all media types that you use for backup
• all locations where media are stored or used.

These should already have been set up in the previous configuration task, Removable Media Drives, but you can still add them now if necessary.

To add a media type now, use Maintain > Media type (see Adding a New Media Type). To add a media location, use Maintain > Location (see Adding a New Media Location).

To add a batch of backup media

1. Select Maintain > Add batch from the ‘Media Details’ window.

The fields are described in detail in To add a media batch.

Generate Simple Backup Scheme

This task generates a simple weekly schedule of backup jobs to perform full and incremental backups of your main filesystems. For many sites this scheme will be all that is required. Larger organizations can build on this framework by adding other backup jobs. The task steps through each mountable filesystem and asks which day of the week a full backup is to be performed. All other filesystems are set up to be incremental backups for that day.

Before you begin

You must have defined all your backup drives. See Removable Media Drives.

backup3G includes several standard retention periods. If you wish to use a different period you must set it up in advance. See To define a retention period.

Steps:

1. backup3G explains what this task is about to do. Press Generate to continue.
2. Choose the backup format (cpio is recommended). This can easily be changed later.
3. Choose the backup drive to use for daily backups.
4. Choose the retention period for each backup. As the backup scheme works to a weekly cycle we recommend that you use a retention period of at least one or two weeks.
5. For each mountable filesystem on this host a confirm screen will display, asking you on which day the full backup is to be run. Press the button corresponding to the day of the week. Unless another filesystem is also chosen for this day all other filesystem backups are assumed to be incremental. If you don’t want to generate a backup scheme for this filesystem, press Skip.
6. Once all filesystems have been dealt with, a backup job is generated for each working day of the week.

The job for each day is displayed, showing one job step for each full and incremental filesystem backup.

Press Print to print a listing of the generated backups for your records. Press Exit when you are finished.

You may wish to customize the generated filesystem backup jobs and backup items. Examples: change the default scheduled time from 23:00; add in the offsite storage location; add or remove backup steps; add new backup jobs to cater for non-filesystem backups. See the major topics in the chapter Setting Up Backups, in particular:

• How to Define a Backup Job
• How to Define a Backup Item

Create Symbolic Links for Methods Run by FSremote

If one or more remote backup hosts are running COSmanager version 2.7 or earlier, you must create symbolic links to certain backup3G programs so that they can be accessed from ~COSmanager/bin.

If you do not have any such remote hosts, there is no need for these symbolic links.

Steps

1. Press Accept to create the symbolic links, or press Exit to skip this task.

Add backup3G Duties to duty3G

If you also have the duty3G application, you can add a batch of duties relating to backup3G. duty3G features more advanced options for scheduling backups, and provides a simpler interface for users who only need access to a few backup3G functions.

If duty3G is already installed, you can add the backup3G duties now. If you install duty3G in future, you can run this task afterwards to add the backup3G duties.

The extra duties take up less than 1 KB of disk space.

Steps

1. Press Accept to add the backup duties to the duty table, or press Skip to skip this task.

Install/Deinstall Enterprise Backup Support

backup3G can back up machines running Windows NT/2000/XP/2003. This task installs special backup, recovery, and communications methods on the UNIX host to support these non-UNIX hosts.

Steps If you don’t need to install any enterprise backup clients, press Exit.

1. If you do wish to install some or all of the enterprise backup clients, Press Choose to select them.
2. Set Action to ‘install’.

Press Accept to install the backup clients.

Appendix B — Checking Job Status Codes

To check the status of all backup jobs on a host:

1. Log in to the host and start backup3G
2. Select Monitor (GUI version) or Monitor backup jobs & maintain logfiles (CUI version).

The Backup Monitor is a dynamic display showing the status of all scheduled and running backups, and all completed backups that have not yet been acknowledged.

To help diagnose a problem you can get more information by highlighting the backup then selecting Logfiles > Display.

This appendix lists suggested actions to be taken for each status code.

Note Your operating system or drives may return other status codes not known to backup3G.

Status of Active Backup and Recovery Jobs

This table lists status codes for jobs that are currently active—that is, they have been scheduled or started but not yet completed.

Table 8 — Status codes for active backup and recovery jobs

Status of Completed Backup and Recovery Jobs.

Table 9 — Status codes for completed backup and recovery jobs

Appendix C — Backup Methods and Drivers

A backup method is the ‘how to’ of a backup step. It contains the command(s) that will write the backup data. backup3G comes with a number of standard backup methods and driver scripts.

These scripts use standard UNIX utilities to provide a uniform set of facilities for backing up and recovering files across a network. In effect the drivers ‘top up’ the basic facilities provided by cpio, dump, and tar.

This appendix describes:

• how multi-part backup methods work
• how to customize the behavior of backup methods by passing optional arguments from a backup item
• features of the driver scripts supplied with backup3G.

Appendix D—Defining Backup Methods describes how to create a new backup method.

Multi-part Backup Methods: How They Work

The recommended method for multi-part backup of filesystems and lists of files and directories is ‘full cpio - MP’. The recommended backup method for multi-part backup of raw partitions and large files is ‘image copy - MP’.

Multi-part backup methods based on FSmcpio call a program FSbusplit to split the backup. FSbusplit uses the size of the file or filesystem and the part size and capacity of the backup medium to calculate how many parts and volumes to split the backup over. FSbusplit uses an algorithm that tries to minimize the number of partitions needed.

By default, FSmcpio can back up files larger than the part size but smaller than the capacity of the volume. FSmcpio simply writes the file to a single larger than usual part. Files larger than the volume’s capacity are rejected with a warning message. To reject files larger than the part size, specify the -B flag to FSmcpio in the Options field of the backup item.

The multi-part methods automatically issue a “change media” request after writing the last part on each volume. The method used to change volumes depends on the logical drive definition. If the last partition on the previous volume was incomplete it is rewritten in full at the start of the new volume.

Although it isn’t mandatory, it is best if multi-part backup steps start writing at the beginning of a volume (backup3G assumes this when it does its capacity calculations). If the multi-part step starts half-way through a volume, it’s likely to write up to the physical end-of-volume, and so the last part will have to be restarted on the next volume.

To sum up, if a multi-part step is not the first in a job to write data, you should insert a ‘change media’ backup step before it to force backup3G to start writing at the start of a new volume.

Each of the multi-part backup methods has a corresponding ‘single-part’ method.

For example:

‘full cpio’

writes a backup step in cpio format to a single tape file or part.

‘full cpio - MP’

writes a backup step in cpio format, if necessary in more than one part or over more than one volume.

We recommend that you use a multi-part backup method where possible, particularly where the directory being backed up:

• won’t fit on a single volume
• is growing, and may not fit in future
• is very large, and you want to speed recovery of selected files by splitting the backup into several parts.

For backups that are guaranteed not to exceed the capacity of a single volume, the advantage of the single-part methods is that they will start up marginally faster.

Capacity and Part Size

You can tune the Multi-part size and Capacity parameters for a media type to make your backups run more efficiently. The following principles should be used as a guide.

• Capacity should be slightly less than the theoretical maximum capacity of the media type, to allow for the label and for variations in the actual tape length among different vendors. A rule-of-thumb is to subtract about 2%.
• Multi-part size should be larger than the size of the largest file.
• One part cannot span volumes, so Multi-part size must not be larger than the capacity of the volume.
• It should be small enough so that the time taken to read or write a part is fairly small (say less than 10 minutes).
• Small parts are more efficient if the data are compressed, either by hardware compression or by use of a compressed backup method. See Data Compression.
• Large parts are faster for recovering a full filesystem but slower for recovering selected files.

If the Multi-part size field is left blank, then the Capacity field will be used in its place. That is, each volume will contain one whole partition.

If both Capacity and Multi-part size are defined, backup3G calculates how many partitions can fit on the output volume, and requests a media change after it has written the last full partition or if an I/O error (End of Media) occurs.

If Capacity is not defined, it defaults to unlimited capacity. This means that partitions will be written to the volume until an I/O error occurs. backup3G assumes this means that end-of-volume has been reached, though it could also be due to some other cause such as a physical defect on the tape.

Caution By default, FSmcpio will back up a file larger than the part size. 
However, if Capacity is null, the partitioning algorithm can’t reject files larger than the real capacity of the volume. 
The backup step will keep requesting a new volume, trying to write the file in full, until it runs out of scratch volumes or is cancelled.
To avoid this, either exclude such files from the backup; set a realistic value for capacity; 
or specify the -B flag in the Options field.

Passing Options to a Backup Method

Each backup item includes an Options field, with which you can pass optional flags and arguments to the backup command as command line parameters.

For example, the cpio backup methods supplied with backup3G accept several flags that change the way backups are done. Some of these can be specified through fields in the backup item. One example is the Index field. This passes the -I flag that instructs FScpio to create an online index. Other flags have no field set aside for them in the ‘Backup item’ prompt form. Some examples:

-s <files> back up this list of files
-x <files> exclude from the backup this list of files
-d perform a deleting backup
-z use the alternate index method ls_index

Example: exclude unwanted files from backup

You have a backup item to backup the filesystem /user2 on host mama using the backup method ‘full cpio - MP’. You want to exclude core and object files and certain temporary files of the form tmpxxxx. To exclude these files from the backup, you would:

1. Select Maintain backup jobs from the backup3G configuration menu.
2. Select Items > Maintain.
3. Select the backup item from the list displayed.
4. Select Maintain > Change.
5. In the Options field, enter -x "*/*.o */core */tmp*"

Figure 45 — Passing arguments to the backup method

These options will be appended to the cpio command at run time.

Note backup3G does not validate any of the options when you create or change the backup item. 
If any of the options are unrecognized or the syntax is incorrect, the backup step will fail when the backup job tries
to execute the command.

You can specify more than one flag. The only limit is the length of the Options field. If you have added your own backup methods to the set provided with backup3G, use Options to take advantage of any flags and features that are recognized by your backup command but aren’t built in to the backup item prompt form.

backup3G Driver Scripts

backup3G includes several backup drivers. These drivers use the standard utilities cpio, dump, and tar, and provide a uniform set of facilities to backup and recover files across a network and to create online indexes. In effect the drivers ‘top up’ the basic facilities provided by cpio, dump, and tar to a common level.

Another driver, FSimage, performs an image copy of a raw disk partition or very large file.

Table 10 shows what features are supported by each driver. Refer to the manual page for more information. Generally we recommend that you use a backup method based on FSmcpio. For particular uses other drivers may be more suitable. See below for notes on working with particular FS backup drivers.

^†writes a 1 KB header followed by a byte-by-byte copy of the data. ^‡dump is not available under AIX or SCO.

Table 10 — Attributes of FS backup drivers