diff options
Diffstat (limited to 'debian/byteback/usr/sbin/byteback-backup')
| -rwxr-xr-x | debian/byteback/usr/sbin/byteback-backup | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/debian/byteback/usr/sbin/byteback-backup b/debian/byteback/usr/sbin/byteback-backup new file mode 100755 index 0000000..22fe0fb --- /dev/null +++ b/debian/byteback/usr/sbin/byteback-backup @@ -0,0 +1,216 @@ +#!/usr/bin/ruby +# +# Back up this system to a byteback-enabled server (just some command line +# tools and SSH setup). We aim to make sure this backups are easy, complete +# and safe for most types of hosting customer. +# +# See 'man byteback' for more information. + +require 'getoptlong' +require 'resolv' + + +def error(message) + STDERR.print "*** #{message}\n" + exit 1 +end + +def verbose(message) + print "#{message}\n" +end + +def help + puts <<EOF +#{$0}: Back up this system to a byteback-enabled server + +Options: + --destination, -d <s>: Backup destination (i.e. user@host:/path) + --source, -s <s>: Source paths (defaults: / and /boot) + --exclude, -x <s>: Exclude paths (defaults: /swap.file, /var/backups/localhost, /var/cache) + --verbose, -v: Show rsync command and progress + --retry-number, -r <n>: Number of retries on error (default: 3) + --retry-delay, -e <n>: Wait number of seconds between retries (default: 1800) + --ssh-key, -k <s>: SSH key for connection (default: /etc/byteback/key) + --help, -h: Show this message +EOF + exit 0 +end + + +opts = GetoptLong.new( + [ '--help', '-h', GetoptLong::NO_ARGUMENT ], + [ '--verbose', '-v', GetoptLong::NO_ARGUMENT ], + [ '--source', '-s', GetoptLong::REQUIRED_ARGUMENT ], + [ '--destination', '-d', GetoptLong::REQUIRED_ARGUMENT ], + [ '--retry-number', '-r', GetoptLong::REQUIRED_ARGUMENT ], + [ '--retry-delay', '-e', GetoptLong::REQUIRED_ARGUMENT ], + [ '--ssh-key' ,'-k', GetoptLong::REQUIRED_ARGUMENT ] +) + +@ssh_key = nil +@destination = nil +@retry_number = 3 +@retry_delay = 1800 +@sources = nil +@excludes = nil + +# Read the default destination +if File.exists?("/etc/byteback/destination") + @destination = File.read("/etc/byteback/destination").chomp +end + +# Set the default SSH key +if File.exists?("/etc/byteback/key") + @ssh_key = "/etc/byteback/key" +end + +# Read in the default sources +if File.exists?("/etc/byteback/sources") + @sources = File.readlines("/etc/byteback/sources").map{|m| m.chomp} +end + +# Read in the default excludes +if File.exists?("/etc/byteback/excludes") + @excludes = File.readlines("/etc/byteback/excludes").map{|m| m.chomp} +end + +begin + opts.each do |opt,arg| + case opt + when '--help' + help = true + when '--verbose' + $VERBOSE = true + when "--source" + @sources ||= [] + @sources << arg + when "--exclude" + @excludes ||= [] + @excludes << arg + when "--destination" + @destination = arg + when "--retry-number" + @retry_number = arg.to_i + when "--retry-delay" + @retry_delay = arg.to_i + when "--ssh-key" + @ssh_key = arg + end + end +rescue => err + # any errors, show the help + warn err.to_s + help = true +end + + +# +# Check our destination +# +if @destination =~ /^(?:(.+)@)?([^@:]+):(.+)?$/ + @destination_user, @destination_host, @destination_path = [$1, $2, $3] +else + error("Destination must be a remote path, e.g. ssh@host.com:/store/backups") +end + +# +# Validate & normalise source directories +# +@sources = ["/"] if @sources.nil? + +error("No sources specified") if @sources.empty? + +@sources = @sources.map do |s| + s = s.gsub(/\/+/,"/") + error("Can't read directory #{s}") unless File.readable?(s) + s +end + +# +# Validate and normalise excludes +# +if @excludes.nil? + @excludes = ["/swap.file", "/var/backups/localhost"] + @excludes << "/var/cache/apt/archives" if File.directory?("/var/cache/apt/archives") +end + +@excludes = @excludes.map do |e| + e.gsub(/\/+/,"/") +end + +error("Must suply --destination or put it into /etc/bytebackup/destination") unless @destination + +# +# Test ssh connection is good before we start +# +error("Could not read ssh key #{@ssh_key}") unless File.readable?(@ssh_key) + +def ssh(*ssh_args) + args = ["ssh", + "-o", "BatchMode=yes", + "-x", "-a", + "-i", @ssh_key, + "-l", @destination_user, + @destination_host + ] + + ssh_args. + map { |a| a ? a : "" } + + print args.map { |a| / /.match(a) ? "\"#{a}\"" : a }.join(" ")+"\n" if $VERBOSE + + system(*args) +end + +error("Could not connect to #{@destination}") unless + ssh("byteback-receive", "--ping", ($VERBOSE ? "--verbose" : "" )) + +# +# Call rsync to copy certain sources, returns exit status (see man rsync) +# +def rsync(*sources) + # Default options include --inplace because we only care about consistency + # at the end of the job, and rsync will do more work for big files without + # it. + # + args = %w(rsync --archive --numeric-ids --delete --inplace --delete --one-file-system --relative) + args += [ "--rsync-path", "rsync --fake-super"] + args += [ "--rsh", "ssh -o BatchMode=yes -x -a -i #{@ssh_key} -l #{@destination_user}"] + args << "--verbose" if $VERBOSE + args += @excludes.map { |x| ["--exclude", x] }.flatten + args += sources + args << @destination + + print args.map { |a| / /.match(a) ? "\"#{a}\"" : a }.join(" ")+"\n" if $VERBOSE + + system(*args) + + return $?.exitstatus +end + +RSYNC_EXIT_STATUSES_TO_RETRY_ON = [10,11,20,21,22,23,24,30] + +# Run the file copy, retrying if necessary +# +loop do + status = rsync(*@sources) + + if status === 0 + break + elsif RSYNC_EXIT_STATUSES_TO_RETRY_ON.include?(status) + if @retry_number > 0 + @retry_number -= 1 + sleep @retry_delay + redo + else + error("Maximum number of rsync retries reached") + end + else + error("Fatal rsync error occurred (#{status})") + end +end + +# Mark the backup as done on the other end +# +error("Backup could not be marked complete") unless + ssh("sudo", "byteback-snapshot", "--snapshot", ($VERBOSE ? "--verbose" : "")) + |