Configuration
By default bdsync-manager reads its configuration from /etc/bdsync-manager.conf. You may specify an alternative location as a command line argument (--config).
The configuration file is structured with a ini-file style. Each section describes one task. The special section DEFAULT can be used to specify defaults that are used for all other sections (if not overwritten explicitely).
Example configuration
See the example configuration file for the definitions of a few typical tasks.
Core settings
source_path
The path of a local blockdevice used as the source for the synchronization.
This setting is required.
target_path
The local or remote path of a file of blockdevice used as the target for the synchronization. This file or blockdevice must exist prior running bdsync-manager. Relative paths are interpretated relative to the current directory (local target) or relative to the remote user's home directory (remote target).
connection_command
A non-empty value of this setting indicates a remote operation. Typically you will want to use ssh for non-interactive remote connections (e.g. connection_command = ssh -p 10022 backup@example.org).
You will need to specify remote_bdsync_bin if connection_command is non-empty.
This setting is optional. The default value is empty.
disabled
This convenience settings allows you to disable tasks easily. You may use any boolean-like value (0/1/yes/no/y/n/true/false/on/off). Alternatively you may also just comment all lines of the task definition (preprending #).
This setting is optional and defaults to False.
create_target_if_missing
bdsync-manager will try to create an empty target file (issuing a touch command) if the target is missing.
This setting simplifies the initial run of a backup.
This setting is optional and defaults to False.
apply_patch_in_place
Instead of storing a binary patch on the target site and applying it afterward, the process is reduced to a single in-place operation.
This will leave a corrupt or inconsistent image behind if the operation is interrupted. Thus this setting is only recommended for the first initial transfer of a blockdevice.
This setting is optional and defaults to False.
bandwidth_limit
Limit the speed of the patch transfer to the destination. This requires the program pv to be installed locally. The bandwidth limit can be suffixed with either b, k, m or g (case independant) denoting the bytes, kibibytes (1024), mebibytes and so on.
This setting is optional. The default value is empty.
bdsync-related settings
local_bdsync_bin
The location of the local bdsync binary (e.g. /usr/local/bin/bdsync).
This setting is required.
remote_bdsync_bin
The location of the remote bdsync binary (e.g. /usr/local/bin/bdsync).
This setting is required if connection_command is specified.
bdsync_args
bdsync allows a few additional arguments for its operation. The arguments given here are applied to the client call and to the patch call. Reasonable examples are --diffsize=resize or --twopass. Arguments are passed to bdsync as-is - you may specify as many as you like separated with spaces.
target_patch_dir
bdsync's binary patches are stored locally or transferred to the remote target host. The path may be absolute or relative to the current directory (local target) or relative to the home directory of the remote user (remote target). You need to create this directory manually. You need to make sure that the directory is on a filesystem with enough free capacity for your bdsync patches. The full size of the largest blockdevice to be transferred is the worst case capacity requiremnt.
This setting is required.
LVM support
You may want to use LVM's snapshotting feature for creating a time-consistent copy of the source blockdevice.
lvm_snapshot_enabled
If this setting evaluates to a true-like value (1/yes/y/true/on) a snapshot is created for the duration of the synchronization.
This setting is optional. It defaults to False
lvm_snapshot_size
The size of the snapshot volume must be specified (see option --size in man lvcreate, e.g. 20G). Please evaluate carefully the amount of changes to be expected for the source blockdevice during the synchronization process. If the snapshot runs out of space it will be invalidated by LVM. Thus the synchronization would fail (without corrupting the target).
This setting is required if lvm_snapshot_enabled is True.
lvm_snapshot_name
The name of the snapshot volume should not conflict with the names of other volumes in the same volume group on the local host. bdsync-manager will stop if it exists (e.g. a remainder of a previous synchronization run). The snapshot will be removed immediately after each task.
This setting is required if lvm_snapshot_enabled is True.
lvm_program_path
The location of the lvm executable is needed for LVM snapshot management.
This setting defaults to /sbin/lvm.