stoney conductor: prov-backup-kvm

Overview

The Provisioning-Backup-KVM Daemon is written in Perl and uses the mechanisms described under stoney core: OpenLDAP directory data organisation.

Workflow

This is the simplified workflow for the Provisioning-Backup-KVM Daemon. The Subroutines (snapshot, merge and retain) are shown later.

Figure 1: Simplified prov-backup-kvm workflow

You can modify/update this workflow by editing File:KVM-Backup-simple.xmi (you may need Umbrello UML Modeller diagram programme for KDE to display the content properly).

Snapshot

Figure 2: Detailed workflow for the snaphshot process

You can edit this workflow with the following file (you may need umbrello to modify it): File:KVM-Backup-Workflow-detailed.xmi

Merge

Figure 2: Detailed workflow for the merge process

You can edit this workflow with the following file (you may need umbrello to modify it): File:KVM-Backup-Workflow-detailed.xmi

Retain

Figure 3: Detailed workflow for the retain process

You can edit this workflow with the following file (you may need umbrello to modify it): File:KVM-Backup-Workflow-detailed.xmi

Exit codes

### Error codes constants
use constant SUCCESS_CODE                               => 0;
use constant UNDEFINED_ERROR                            => 1; # Always the first!
use constant MISSING_PARAMETER_IN_CONFIG_FILE           => 2;
use constant CONFIGURED_RAM_DISK_IS_NOT_VALUD           => 3;
use constant NOT_ENOUGH_SPACE_ON_RAM_DISK               => 4;
use constant CANNOT_SAVE_MACHINE_STATE                  => 5;
use constant CANNOT_WRITE_TO_BACKUP_LOCATION            => 6;
use constant CANNOT_COPY_FILE_TO_BACKUP_LOCATION        => 7;
use constant CANNOT_COPY_IMAGE_TO_BACKUP_LOCATION       => 8;
use constant CANNOT_COPY_XML_TO_BACKUP_LOCATION         => 9;
use constant CANNOT_COPY_BACKEND_FILE_TO_BACKUP_LOCATION=> 10;
use constant CANNOT_MERGE_DISK_IMAGES                   => 11;
use constant CANNOT_REMOVE_OLD_DISK_IMAGE               => 12;
use constant CANNOT_REMOVE_FILE                         => 13;
use constant CANNOT_CREATE_EMPTY_DISK_IMAGE             => 15;
use constant CANNOT_RENAME_DISK_IMAGE                   => 16;
use constant CANNOT_CONNECT_TO_BACKEND                  => 17;
use constant WRONG_STATE_INFORMATION                    => 18;
use constant CANNOT_SET_DISK_IMAGE_OWNERSHIP            => 19;
use constant CANNOT_SET_DISK_IMAGE_PERMISSION           => 20;
use constant CANNOT_RESTORE_MACHINE                     => 21;
use constant CANNOT_LOCK_MACHINE                        => 22;
use constant CANNOT_FIND_MACHINE                        => 23;
use constant CANNOT_COPY_STATE_FILE_TO_RETAIN           => 24;
use constant RETAIN_ROOT_DIRECTORY_DOES_NOT_EXIST       => 25;
use constant BACKUP_ROOT_DIRECTORY_DOES_NOT_EXIST       => 26;
use constant CANNOT_CREATE_DIRECTORY                    => 27;
use constant CANNOT_SAVE_XML                            => 28;
use constant CANNOT_SAVE_BACKEND_ENTRY                  => 29;
use constant CANNOT_SET_DIRECTORY_OWNERSHIP             => 30;
use constant CANNOT_SET_DIRECTORY_PERMISSION            => 31;
use constant CANNOT_FIND_CONFIGURATION_ENTRY            => 32;
use constant BACKEND_XML_UNCONSISTENCY                  => 33;
use constant CANNOT_CREATE_TARBALL                      => 34;
use constant UNSUPPORTED_FILE_TRANSFER_PROTOCOL         => 35;
use constant UNKNOWN_BACKEND_TYPE                       => 36;
use constant MISSING_NECESSARY_FILES                    => 37;
use constant CORRUPT_DISK_IMAGE_FOUND                   => 38;
use constant UNSUPPORTED_CONFIGURATION_PARAMETER        => 39;
use constant CANNOT_MOVE_DISK_IMAGE_TO_ORIGINAL_LOCATION=> 40;
use constant CANNOT_DEFINE_MACHINE                      => 41;
use constant CANNOT_START_MACHINE                       => 42;
use constant CANNOT_WORK_ON_UNDEFINED_OBJECT            => 43;
use constant CANNOT_READ_STATE_FILE                     => 44;
use constant CANNOT_READ_XML_FILE                       => 45;
use constant NOT_ALL_FILES_DELETED_FROM_RETAIN_LOCATION => 46;
use constant NOT_ENOUGH_DISK_SPACE                      => 47;
use constant NO_DISK_SPACE_INFORMATION                  => 48;

Next steps

• Change the behaviour of the snapshot/merge process
  • No longer merge the original file into the new one but merge (commit) backing store file back into original one
    • Like that we are able to reduce the backup (merge) time a lot.
    • Needs different behaviour for save -> copy/move -> create new image -> restore -> merge