Changes
/* Communication through backend */
[[File:Daemon-communication.png|500px|thumbnail|none|Figure 1: Communication between the control instance and the prov-backup-kvm daemon through the LDAP backend]]
=== Control-Instance Daemon Interaction for creating a Backup with LDIF Examples ===
The step numbers correspond with the graphical overview from above.
==== Step 00: Backup Configuration for a virtual machine ====
<pre>
# The following backup configuration says, that the backup should be done daily, at 03:00 hours (localtime).
# * * * * * command to be executed
# - - - - -
# | | | | |
# | | | | +----- day of week (0 - 6) (Sunday=0)
# | | | +------- month (1 - 12)
# | | +--------- day of month (1 - 31)
# | +----------- hour (0 - 23)
# +------------- min (0 - 59)
# localtime in the crontab entry
dn: ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
objectclass: top
objectclass: organizationalUnit
objectclass: sstVirtualizationBackupObjectClass
objectclass: sstCronObjectClass
ou: backup
description: This sub tree contains the backup plan for the virtual machine kvm-005.
sstCronMinute: 0
sstCronHour: 3
sstCronDay: *
sstCronMonth: *
sstCronDayOfWeek: *
sstCronActive: TRUE
sstBackupRootDirectory: file:///var/backup/virtualization
sstBackupRetainDirectory: file:///var/virtualization/retain
sstBackupRamDiskLocation: file:///mnt/ramdisk-test
sstVirtualizationDiskImageFormat: qcow2
sstVirtualizationDiskImageOwner: root
sstVirtualizationDiskImageGroup: vm-storage
sstVirtualizationDiskImagePermission: 0660
sstBackupNumberOfIterations: 1
sstVirtualizationVirtualMachineForceStart: FALSE
sstVirtualizationBandwidthMerge: 0
</pre>
==== Step 01: Initialize Backup Sub Tree (Control instance daemon) ====
The sub tree ''' ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch''' reflects the time, when the backup is planned (in the form of [YYYY][MM][DD]T[hh][mm][ss]Z ([http://en.wikipedia.org/wiki/ISO_8601 ISO 8601]) and it should be written at the time, when the backup is planned and should be executed. The section '''20121002T010000Z''' means the following:
* Year: 2012
* Month: 10
* Day of Month: 02
* Hour of Day: 01
* Minutes: 00
* Seconds: 00
Please be aware the the time is to be written in UTC (see also the comment in the LDIF example below).
<pre>
# This entry is the place holder for the backup, which is to be executed at 03:00 hours (localtime with daylight-saving). This
# leads to the 20121002T010000Z timestamp (which is written in UTC).
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
objectclass: top
objectclass: sstProvisioning
objectclass: organizationalUnit
ou: 20121002T010000Z
sstProvisioningExecutionDate: 0
sstProvisioningMode: initialize
sstProvisioningReturnValue: 0
sstProvisioningState: 20121002T014513Z
</pre>
==== Step 02: Finalize the Initialization (Control instance daemon) ====
<pre>
# The attribute sstProvisioningState is updated with current time by the fc-brokerd, when sstProvisioningMode is modified.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 20121002T010001Z
-
replace: sstProvisioningMode
sstProvisioningMode: initialized
</pre>
==== Step 03: Start the Snapshot Process (Control instance daemon) ====
With the setting of the '''sstProvisioningMode''' to '''snapshot''', the actual backup process is kicked off by the Control instance daemon.
<pre>
# The attribute sstProvisioningState is set to zero by the fc-brokerd, when sstProvisioningMode is modified to
# snapshot (this way the Provisioning-Backup-VKM daemon knows, that it must start the snapshotting process).
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 0
-
replace: sstProvisioningMode
sstProvisioningMode: snapshot
</pre>
==== Step 04: Starting the Snapshot Process (Provisioning-Backup-KVM daemon) ====
As soon as the Provisioning-Backup-KVM daemon receives the snapshot command, it sets the '''sstProvisioningMode''' to '''snapshotting''' to tell the Control instance daemon and other interested parties, that it is snapshotting the virtual machine or virtual machine template.
<pre>
# The attribute sstProvisioningMode is set to snapshotting by the Provisioning-Backup-VKM daemon.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningMode
sstProvisioningMode: snapshotting
</pre>
==== Step 05: Finalizing the Snapshot Process (Provisioning-Backup-KVM daemon) ====
As soon as the Provisioning-Backup-KVM daemon has executed the snapshot command, it sets the '''sstProvisioningMode''' to '''snapshotted''', the '''sstProvisioningState''' to the current timestamp (UTC) and '''sstProvisioningReturnValue''' to zero to tell the Control instance daemon and other interested parties, that the snapshot of the virtual machine or virtual machine template is finished.
<pre>
# The attribute sstProvisioningState is set with the current timestamp by the Provisioning-Backup-VKM daemon, when
# the attributes sstProvisioningReturnValue and sstProvisioningMode are set.
# With this combination, the fc-brokerd knows, that it can proceed.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 20121002T010011Z
-
replace: sstProvisioningReturnValue
sstProvisioningReturnValue: 0
-
replace: sstProvisioningMode
sstProvisioningMode: snapshotted
</pre>
==== Step 06: Start the Merge Process (Control instance daemon) ====
With the setting of the '''sstProvisioningMode''' to '''merge''', the Control instance daemon tells the Provisioning-Backup-KVM daemon to merge the backing file disk image back into the current disk image.
<pre>
# The attribute sstProvisioningState is set to zero by the fc-brokerd, when sstProvisioningMode is modified to
# merge (this way the Provisioning-Backup-VKM daemon knows, that it must start the merging process).
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 0
-
replace: sstProvisioningMode
sstProvisioningMode: merge
</pre>
==== Step 07: Starting the Merge Process (Provisioning-Backup-KVM daemon) ====
As soon as the Provisioning-Backup-KVM daemon receives the merge command, it sets the '''sstProvisioningMode''' to '''merging''' to tell the Control instance daemon and other interested parties, that it is merging the virtual machine or virtual machine template.
<pre>
# The attribute sstProvisioningMode is set to merging by the Provisioning-Backup-VKM daemon.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningMode
sstProvisioningMode: merging
</pre>
==== Step 08: Finalizing the Merging Process (Provisioning-Backup-KVM daemon) ====
As soon as the Provisioning-Backup-KVM daemon has executed the merge command, it sets the '''sstProvisioningMode''' to '''merged''', the '''sstProvisioningState''' to the current timestamp (UTC) and '''sstProvisioningReturnValue''' to zero to tell the Control instance daemon and other interested parties, that the merging of the virtual machine or virtual machine template is finished.
<pre>
# The attribute sstProvisioningState is set with the current timestamp by the Provisioning-Backup-VKM daemon, when
# the attributes sstProvisioningReturnValue and sstProvisioningMode are set.
# With this combination, the fc-brokerd knows, that it can proceed.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 20121002T010500Z
-
replace: sstProvisioningReturnValue
sstProvisioningReturnValue: 0
-
replace: sstProvisioningMode
sstProvisioningMode: merged
</pre>
==== Step 09: Start the Retain Process (Control instance daemon) ====
With the setting of the '''sstProvisioningMode''' to '''retain''', the Control instance daemon tells the Provisioning-Backup-KVM daemon to retain (copy and then delete) all the necessary files to the configured backup location.
<pre>
# The attribute sstProvisioningState is set to zero by the fc-brokerd, when sstProvisioningMode is modified to
# retain (this way the Provisioning-Backup-VKM daemon knows, that it must start the retaining process).
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 0
-
replace: sstProvisioningMode
sstProvisioningMode: retain
</pre>
==== Step 10: Starting the Retain Process (Provisioning-Backup-KVM daemon) ====
As soon as the Provisioning-Backup-KVM daemon receives the retain command, it sets the '''sstProvisioningMode''' to '''retaining''' to tell the Control instance daemon and other interested parties, that it is retaining the necessary files to the configured backup location.
<pre>
# The attribute sstProvisioningMode is set to retaining by the Provisioning-Backup-VKM daemon.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningMode
sstProvisioningMode: retaining
</pre>
==== Step 11: Finalizing the Retaing Process (Provisioning-Backup-KVM daemon) ====
As soon as the Provisioning-Backup-KVM daemon has executed the retain command, it sets the '''sstProvisioningMode''' to '''retained''', the '''sstProvisioningState''' to the current timestamp (UTC) and '''sstProvisioningReturnValue''' to zero to tell the Control instance daemon and other interested parties, that the retaining of all the necessary files to the configured backup location is finished.
<pre>
# The attribute sstProvisioningState is set with the current timestamp by the Provisioning-Backup-VKM daemon, when
# the attributes sstProvisioningReturnValue and sstProvisioningMode are set.
# With this combination, the fc-brokerd knows, that it can proceed.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 20121002T012000Z
-
replace: sstProvisioningReturnValue
sstProvisioningReturnValue: 0
-
replace: sstProvisioningMode
sstProvisioningMode: retained
</pre>
==== Step 12: Finalizing the Backup Process (Control instance daemon) ====
As soon as the Control instance daemon notices, that the attribute '''sstProvisioningMode''' ist set to '''retained''', it sets the '''sstProvisioningMode''' to '''finished''' and the '''sstProvisioningState''' to the current timestamp (UTC). All interested parties now know, that the backup process is finished, there for a new backup process could be started.
<pre>
# The attribute sstProvisioningState is updated with current time by the fc-brokerd, when sstProvisioningMode is
# set to finished.
# All interested parties now know, that the backup process is finished, there for a new backup process could be started.
dn: ou=20121002T010000Z,ou=backup,sstVirtualMachine=kvm-005,ou=virtual machines,ou=virtualization,ou=services,o=stepping-stone,c=ch
changetype: modify
replace: sstProvisioningState
sstProvisioningState: 20121002T012001Z
-
replace: sstProvisioningMode
sstProvisioningMode: finished
</pre>
= State of the art =
