X-Git-Url: http://git.tuebingen.mpg.de/?p=dss.git;a=blobdiff_plain;f=dss.ggo;h=46b4271936d1ae7e1fe7e958d0ecc7ce55ed876b;hp=8dd7090b19c857aeb83c4ecd4cfda8d86f8f7a7b;hb=a002cd5d2c29369caf8782a607cecedcb9cbafee;hpb=a31c35b86e485c6c1feeaf9e1957e3d3ab52c7e5 diff --git a/dss.ggo b/dss.ggo index 8dd7090..46b4271 100644 --- a/dss.ggo +++ b/dss.ggo @@ -1,56 +1,73 @@ # package "dss" -version "0.0.1" -purpose "the dyadic snapshot scheduler" +version "0.0.3" +purpose "the dyadic snapshot scheduler +dss creates hardlink-based snapshots of a given directory on a remote +or local host using rsync's link-dest feature. +" + +######################### +section "General options" +######################### -option "config_file" c +option "config-file" c #~~~~~~~~~~~~~~~~~~~~~ "(default='~/.dssrc')" - - string typestr="filename" - optional - -section "Logging" -#~~~~~~~~~~~~~~~~ - -option "loglevel" l -#~~~~~~~~~~~~~~~~~~ - -"set loglevel (0-6)" - - int typestr="level" - default="4" - optional - -option "logfile" - -#~~~~~~~~~~~~~~~~~ - -"logfile for the dss daemon process" - - string typestr="filename" - optional +string typestr="filename" +optional +details=" + Options may be given at the command line or in the + configuration file. As usual, if an option is given both at + the command line and in the configuration file, the command + line option takes precedence. +" option "daemon" d #~~~~~~~~~~~~~~~~ -"run as background daemon" +"Run as background daemon" flag off dependon="logfile" details=" - Note that dsss refuses to start in daemon mode if no logfile - was specified. + Note that dss refuses to start in daemon mode if no logfile + was specified. This option is mostly useful in conjuction + with the -R option described below. " -option "dry_run" D +option "dry-run" D #~~~~~~~~~~~~~~~~~ -"only print what would be done" +"Only print what would be done" flag off details=" - This flag does not makes sense for all commands. The run + This flag does not make sense for all commands. The run command refuses to start if this option was given. The ls command silently ignores this flag. " +################# +section "Logging" +################# + +option "loglevel" l +#~~~~~~~~~~~~~~~~~~ +"Set loglevel (0-6)" +int typestr="level" +default="3" +optional +details=" + Lower values mean less verbose logging. +" + +option "logfile" - +#~~~~~~~~~~~~~~~~~ +"Logfile for the dss daemon process" +string typestr="filename" +optional +details=" + This option is mostly useful for the run command if --daemon + is also given. +" + defgroup "command" #================= groupdesc=" @@ -61,155 +78,164 @@ required groupoption "create" C #~~~~~~~~~~~~~~~~~~~~~ -"create a new snapshot" +"Create a new snapshot" group="command" details=" - Execute the rsync command to create a new snapshot.Mote that this + Execute the rsync command to create a new snapshot. Note that this command does not care about free disk space. " groupoption "prune" P #~~~~~~~~~~~~~~~~~~~~ -"remove a redundant snapshot" +"Remove a redundant snapshot" group="command" details=" A snapshot is considered redundant if it ether belongs to - an interval greater than the maximum nuber of intervals, + an interval greater than the maximum number of intervals, or if it belongs to an interval that already contains more than the desired number of snapshots. " groupoption "ls" L #~~~~~~~~~~~~~~~~~ -"print a list of all snapshots" +"Print a list of all snapshots" group="command" details=" - The list will contain all snapshots not matter of their state, - i.e. incomplete snapshots and snapshots being deleted will + The list will contain all snapshots no matter of their state, + i. e. incomplete snapshots and snapshots being deleted will also be listed. " groupoption "run" R #~~~~~~~~~~~~~~~~~~ -"start creating and pruning snapshots" +"Start creating and pruning snapshots" group="command" details=" This is the main mode of operation. Snapshots will be created as needed and pruned automatically. " -section "rsync-related options" -#============================== +############################### +section "Rsync-related options" +############################### -option "remote_user" U +option "remote-host" H #~~~~~~~~~~~~~~~~~~~~~ +"Remote host" +string typestr="hostname" +default="localhost" +optional +details=" + If this option is given and its value differs from the local + host, then rsync uses ssh. Make sure there is no password + needed for the ssh connection. To achieve that, use public key + authentication for ssh and, if needed, set the remote user name + by using the --remote-user option. +" -"remote user name (default: current user)" - - string typestr="username" - optional - -option "remote_host" H +option "remote-user" U #~~~~~~~~~~~~~~~~~~~~~ +"Remote user name (default: current user)" +string typestr="username" +optional +details=" + Set this if the user running dss is different from the + user at the remote host when using ssh. +" -"remote host" - - string typestr="hostname" - default="localhost" - optional - -option "source_dir" - +option "source-dir" - #~~~~~~~~~~~~~~~~~~~~ +"The data directory" +string typestr="dirname" +optional +details=" + The directory on the remote host from which snapshots are + taken. Of course, the user specified as --remote-user must + have read access to this directory. +" -"directory to backup on the remote host" - - string typestr="dirname" - optional - -option "dest_dir" - +option "dest-dir" - #~~~~~~~~~~~~~~~~~~ +"Snapshot dir" +string typestr="dirname" +optional +details=" + The destination directory on the local host where snapshots + will be written. This must be writable by the user who runs + dss. +" -"snapshots dir on the local host" - - string typestr="dirname" - optional - -option "rsync_option" O +option "rsync-option" O #~~~~~~~~~~~~~~~~~~~~~~ +"Further rsync options" +string typestr="option" +optional +multiple +details=" + These option may be given multiple times. The arguments passed + to that option are passed verbatim to the rsync command. +" -"further rsync options that are passed -verbatim to the rsync command." - - string typestr="option" - optional - multiple - - -option "exclude_patterns" e -#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -"rsync exclude patterns" - - string typestr="path" - optional - +option "exclude-patterns" e +#~~~~~~~~~~~~~~~~~~~~~~~~~~ +"Rsync exclude patterns" +string typestr="path" +optional +################### section "Intervals" -#~~~~~~~~~~~~~~~~~~ +################### -text " -dss snapshot aging is implemented in terms of intervals. There are -two command line options related to intervals: the duration of a -'unit' interval and the number of those unit intervals. - -dss removes any snapshots older than the given number of intervals -times the duration of an unit interval and tries to keep the following -number of snapshots per interval: - - interval number number of snapshots - =============================================== - 0 2 ^ (num_intervals - 1) - 1 2 ^ (num_intervals - 2) - 2 2 ^ (num_intervals - 3) - ... - num_intervals - 2 2 - num_intervals - 1 1 - num_intervals 0 - -In other words, the oldest snapshot will at most be unit_interval * -num_intervala old (= 5 days * 4 = 20 days if default values are used). -Moreover, there are at most 2^num_intervals - 1 snapshots in total -(i.e. 31 by default). Observe that you have to create at least -num_intervals snapshots each interval for this to work out. " - -option "unit_interval" u +option "unit-interval" u #~~~~~~~~~~~~~~~~~~~~~~~ -"the duration of a unit interval" - - int typestr="days" - default="4" - optional +"The duration of a unit interval" +int typestr="days" +default="4" +optional +details=" + dss snapshot aging is implemented in terms of intervals. There are + two command line options related to intervals: the duration of a + \"unit\" interval and the number of those unit intervals. + + dss removes any snapshots older than the given number of intervals + times the duration of a unit interval and tries to keep the following + number of snapshots per interval: + + interval number number of snapshots + =============================================== + 0 2 ^ (num-intervals - 1) + 1 2 ^ (num-intervals - 2) + 2 2 ^ (num-intervals - 3) + ... + num-intervals - 2 2 + num-intervals - 1 1 + num-intervals 0 + + In other words, the oldest snapshot will at most be unit_interval * + num_intervals old (= 5 days * 4 = 20 days if default values are used). + Moreover, there are at most 2^num_intervals - 1 snapshots in total + (i. e. 31 by default). Observe that you have to create at least + 2 ^ (num_intervals - 1) snapshots each interval for this to work out. +" -option "num_intervals" n +option "num-intervals" n #~~~~~~~~~~~~~~~~~~~~~~~ -"the number of unit intervals" - - int typestr="num" - default="5" - optional +"The number of unit intervals" +int typestr="num" +default="5" +optional +############### section "Hooks" -#============== +############### -option "pre_create_hook" r +option "pre-create-hook" r #~~~~~~~~~~~~~~~~~~~~~~~~~~ "Executed before snapshot creation" - - string typestr="command" - default="/bin/true" - optional - +string typestr="command" +default="/bin/true" +optional details=" - Execute this command before trying to create a new snapshot + Execute this command before trying to create a new snapshot. If this command returns with a non-zero exit status, do not perform the backup. One possible application of this is to return non-zero during office hours in order to not slow down @@ -217,14 +243,12 @@ details=" " -option "post_create_hook" o +option "post-create-hook" o #~~~~~~~~~~~~~~~~~~~~~~~~~~ "Executed after snapshot creation" - - string typestr="command" - default="/bin/true" - optional - +string typestr="command" +default="/bin/true" +optional details=" Execute this after a snapshot has successfully been created The return value on the command is ignored. For instance one @@ -232,32 +256,37 @@ details=" usage patterns in order to store them in a database for further treatment. " -option "creation_sleep" s -#~~~~~~~~~~~~~~~~~~~~~~~~ -"sleep interval" - int typestr="minutes" - default="60" - optional +############################### +section "Disk space monitoring" +############################### +option "min-free-mb" m +#~~~~~~~~~~~~~~~~~~~~~ +"Minimal amount of free disk space" +int typestr="megabytes" +default="100" +optional details=" - The sleep interval for snapshot creation in minutes. - The daemon will, in an endlees loop, create a snapshot and - then sleep that many minutes. -" - + If less than this many megabytes of space is available on + the file system containing the destination directory, \"dss + --run\" will suspend the currently running rsync process and will + start to remove snapshots, starting from the oldest snapshot, + until the free disk space exceeds this value. See also the + --min_free_percent option. -option "min_free" m -#~~~~~~~~~~~~~~~~~~ - -"minimal amount of free space" + A value of zero deactivates this check. - int typestr="gigabytes" - default="50" - optional +" +option "min-free-percent" p +#~~~~~~~~~~~~~~~~~~~~~~~~~~ +"Minimal percent of free disk space" +int typestr="percent" +default="2" +optional details=" - If less that this many gigabytes of space is available, - dss will start to remove snapshots (starting from the oldest - snapshot) until the free disk space exeecds this value. + See --min-free-mb. Note that it is not recommended to set both + --min-free-mb and --min-free-percent to zero as this will + cause your file system to fill up quickly. "