dirvish - Disk based virtual image network backup system
dirvish --vault vault [ OPTIONS ]
Create a backup image of a client directory tree.
Each image is a directory containing transfer log, summary, tree and if
transfer errors were detected an rsync_error file. The transfer log
retains the the output of any pre and post processing commands and the
rsync log listing all files that were changed or added with some
statistical information. The summary file contains all the information
about how the image was created and meta-data for managing the image in
config file format. Tree is the copy of the client tree.
The client directory tree is compared with an existing image to create
a new image. Unchanged files are shared between images. For changed
files only those parts that actually change are transfered over the
network. Unchanged portions of files are copied from the reference
The resulting images contain complete copies of the original trees
preserving ownership and file permissions. In this way even though the
backups are made incrementally, each image can be used independently
for restores or to make removable-media off-site copies or archives.
The removal of an image will have no effect on other images.
Each option on the command line may be specified any number of times.
Those options that support lists in the config files will accumulate
all of their arguments otherwise each specification will override the
As configuration files are loaded they may override options on the
Each option may be unambiguously abbreviated.
Specify a branch to use.
A branch is a sequence of images.
If a vault has been specified either here or with --vault the
first time this option is used it will attempt to load the
config file branch_name or branch_name.conf from the vault.
Load options from the specified file.
If this precedes --vault the --vault option will not load it’s
own config file.
If vault has been set and config-file is a bare filename the
presence of one in the vault will take precedence over one in
the current directory. To specify one in the current directory
after --vault use ./ to precede the name.
The master configuration file will be read prior to processing
Specify a time for the image to expire.
See Time::ParseDate(3pm) for details.
This does not actually expire anything. What it does do is add
an Expire: field to the image summary file containing an
absolute time so that a dirvish-expire or another tool outside
of dirvish can decide when to remove old images.
Specify a name for the image.
image_name is passed through POSIX::strftime
See strftime(3) for details.
Time to use when creating the image name.
If an absolute time without a date is provided it will be forced
into the past. If this isn’t set the current time will be used.
See Time::ParseDate(3pm) for details.
--init Create an initial image.
Create the image entirely from the source tree without the use
of a reference image.
Don’t actually do anything.
Process all configuration files, options and tests then produce
a summary/configuration file on standard output and exit.
Specify an existing image or a branch from which to create the
If a branch_name is specified, the last existing image from its
history file will be used. A branch will take precedence over
an image of the same name.
Reset the values in an accumulating option.
Specify summary format.
A short summary will only include final used values. A long
summary will include all configuration values.
Default value: short
Specify the vault to store the image in.
If not preceeded by --config this will attempt to load the
config file default or default.conf within the vault.
If branch_name is specified here this will behave exactly like
the --branch option and branch_name or branch_name.conf will be
attempted instead of default.conf.
Print version string and exit.
To facilitate further automation and integration of dirvish with other
tools dirvish provides rationalised exit codes. The exit codes are
range based. While the code for a specific error may change from one
version to another it will remain within the specified range. So don’t
test for specific exit codes but instead test for a range of values.
To the degree possible higher value ranges indicate more severe errors.
1-19 The backup job reported warnings.
20-39 An error occurred during index generation and cleanup.
40-49 A post-client or post-server command could not be run.
50-59 The post-client command reported an error. Its exit code modulo
10 is added to 50
60-69 The post-server command reported an error. Its exit code modulo
10 is added to 60
70-79 A post-client or post-server command could not be run.
80-89 The pre-server command reported an error. Its exit code modulo
10 is added to 80
90-99 The pre-server command reported an error. Its exit code modulo
10 is added to 90
Rsync encountered a non-fatal error.
Rsync encountered a fatal error.
An error was encountered in loading a configuration file.
An error was detected in the configuration.
255 Incorrect usage.
alternate master configuration file.
master configuration file.
client configuration file.
default vault configuration file.
branch configuration file.
branch history file.
image creation summary.
image creation log.
actual image of source directory tree.
Error output from rsync if errors or warnings were detected.
Dirvish was created by J.W. Schultz of Pegasystems Technologies.
BUGS AND ISSUES
Fields set in configuration files will override command line options
that have been set before the file is read. This behaviour while
consistent may occasionally confuse. For this reason most command line
options should be specified after any options that may cause a
configuration file to be loaded.
In order to preserve permissions it is necessary for dirvish to run as
root on the backup server.
The root user must have non-interactive ssh access to the client
systems. It is not necessary that this access be as the root user on
File ownership is preserved using numeric values so it is not necessary
to have user accounts on the backup server. Making the vaults network
accessible using protocols that map UIDs based on names instead of
number could allow access controls on files to be violated.
Making the vaults writable by users will compromise the integrity of
the backups. Therefore any access to the vaults by users should be
done through a read-only mount.