contrib/zcp/autosnap.lua

   1 -- Recursively snapshot every dataset with a given property
   2 --
   3 -- Usage: zfs program <pool> autosnap.lua -- [-n] [-p <property>] <snapshot>
   4
   5 results = {}
   6
   7 args = ...
   8 argv = args["argv"]
   9 usage = [[
  10
  11
  12 usage: zfs program <pool> autosnap.lua -- [-n] [-p <property>] <snapshot>
  13
  14         -n: performs checks only, does not take snapshots
  15         -p <property>: property to check. [default: com.sun:auto-snapshot]
  16         <snapshot>: root snapshot to create [example: tank/data@backup]
  17 ]]
  18
  19 property = "com.sun:auto-snapshot"
  20 noop = false
  21 root_snap = nil
  22
  23 for i, arg in ipairs(argv) do
  24         if arg == "-n" then
  25                 noop = true
  26         elseif arg == "-p" then
  27         elseif argv[i-1] == "-p" then
  28                 property = arg
  29         else
  30                 root_snap = arg
  31         end
  32 end
  33
  34 if root_snap == nil or property == nil then
  35         error(usage)
  36 end
  37
  38 root_ds_name = ""
  39 snap_name = ""
  40 for i = 1, #root_snap do
  41         if root_snap:sub(i, i) == "@" then
  42                 root_ds_name = root_snap:sub(1, i-1)
  43                 snap_name = root_snap:sub(i+1, root_snap:len())
  44         end
  45 end
  46
  47 function auto_snap(root)
  48         auto, source = zfs.get_prop(root, property)
  49         if auto == "true" then
  50                 ds_snap_name = root .. "@" .. snap_name
  51                 err = 0
  52                 if noop then
  53                         err = zfs.check.snapshot(ds_snap_name)
  54                 else
  55                         err = zfs.sync.snapshot(ds_snap_name)
  56                 end
  57                 results[ds_snap_name] = err
  58         end
  59         for child in zfs.list.children(root) do
  60                 auto_snap(child)
  61         end
  62 end
  63
  64 auto_snap(root_ds_name)
  65 err_txt = ""
  66 for ds, err in pairs(results) do
  67         if err ~= 0 then
  68                 err_txt = err_txt .. "failed to create " .. ds .. ": " .. err .. "\n"
  69         end
  70 end
  71 if err_txt ~= "" then
  72         error(err_txt)
  73 end
  74
  75 return results