diff --git a/README.md b/README.md index 9c4e6ba..b66deac 100644 --- a/README.md +++ b/README.md @@ -108,6 +108,7 @@ syncoid root@remotehost:data/images/vm backup/images/vm Which would pull-replicate the filesystem from the remote host to the local system over an SSH tunnel. Syncoid supports recursive replication (replication of a dataset and all its child datasets) and uses mbuffer buffering, lzop compression, and pv progress bars if the utilities are available on the systems used. +If ZFS supports resumeable send/receive streams on both the source and target those will be enabled as default. ##### Syncoid Command Line Options @@ -147,6 +148,10 @@ Syncoid supports recursive replication (replication of a dataset and all its chi This argument tells syncoid to restrict itself to existing snapshots, instead of creating a semi-ephemeral syncoid snapshot at execution time. Especially useful in multi-target (A->B, A->C) replication schemes, where you might otherwise accumulate a large number of foreign syncoid snapshots. ++ --no-resume + + This argument tells syncoid to not use resumeable zfs send/receive streams. + + --dumpsnaps This prints a list of snapshots during the run. diff --git a/syncoid b/syncoid index 0654ac3..784bd90 100755 --- a/syncoid +++ b/syncoid @@ -19,7 +19,7 @@ use Sys::Hostname; my %args = ('sshkey' => '', 'sshport' => '', 'sshcipher' => '', 'sshoption' => [], 'target-bwlimit' => '', 'source-bwlimit' => ''); GetOptions(\%args, "no-command-checks", "monitor-version", "compress=s", "dumpsnaps", "recursive|r", "source-bwlimit=s", "target-bwlimit=s", "sshkey=s", "sshport=i", "sshcipher|c=s", "sshoption|o=s@", - "debug", "quiet", "no-stream", "no-sync-snap") or pod2usage(2); + "debug", "quiet", "no-stream", "no-sync-snap", "no-resume") or pod2usage(2); my %compressargs = %{compressargset($args{'compress'} || 'default')}; # Can't be done with GetOptions arg, as default still needs to be set @@ -46,6 +46,7 @@ my $rawsourcefs = $args{'source'}; my $rawtargetfs = $args{'target'}; my $debug = $args{'debug'}; my $quiet = $args{'quiet'}; +my $resume = !$args{'no-resume'}; my $zfscmd = '/sbin/zfs'; my $sshcmd = '/usr/bin/ssh'; @@ -161,32 +162,52 @@ sub syncdataset { # does the target filesystem exist yet? my $targetexists = targetexists($targethost,$targetfs,$targetisroot); - # build hashes of the snaps on the source and target filesystems. + my $receiveextraargs = ""; + my $receivetoken; + if ($resume) { + # save state of interrupted receive stream + $receiveextraargs = "-s"; - %snaps = getsnaps('source',$sourcehost,$sourcefs,$sourceisroot); + if ($targetexists) { + # check remote dataset for receive resume token (interrupted receive) + $receivetoken = getreceivetoken($targethost,$targetfs,$targetisroot); - if ($targetexists) { - my %targetsnaps = getsnaps('target',$targethost,$targetfs,$targetisroot); - my %sourcesnaps = %snaps; - %snaps = (%sourcesnaps, %targetsnaps); + if ($debug && defined($receivetoken)) { + print "DEBUG: got receive resume token: $receivetoken: \n"; + } + } } - if (defined $args{'dumpsnaps'}) { - print "merged snapshot list of $targetfs: \n"; - dumphash(\%snaps); - print "\n\n\n"; - } - - # create a new syncoid snapshot on the source filesystem. my $newsyncsnap; - if (!defined $args{'no-sync-snap'}) { - $newsyncsnap = newsyncsnap($sourcehost,$sourcefs,$sourceisroot); - } else { - # we don't want sync snapshots created, so use the newest snapshot we can find. - $newsyncsnap = getnewestsnapshot($sourcehost,$sourcefs,$sourceisroot); - if ($newsyncsnap eq 0) { - warn "CRITICAL: no snapshots exist on source $sourcefs, and you asked for --no-sync-snap.\n"; - return 0; + + # skip snapshot checking/creation in case of resumed receive + if (!defined($receivetoken)) { + # build hashes of the snaps on the source and target filesystems. + + %snaps = getsnaps('source',$sourcehost,$sourcefs,$sourceisroot); + + if ($targetexists) { + my %targetsnaps = getsnaps('target',$targethost,$targetfs,$targetisroot); + my %sourcesnaps = %snaps; + %snaps = (%sourcesnaps, %targetsnaps); + } + + if (defined $args{'dumpsnaps'}) { + print "merged snapshot list of $targetfs: \n"; + dumphash(\%snaps); + print "\n\n\n"; + } + + if (!defined $args{'no-sync-snap'}) { + # create a new syncoid snapshot on the source filesystem. + $newsyncsnap = newsyncsnap($sourcehost,$sourcefs,$sourceisroot); + } else { + # we don't want sync snapshots created, so use the newest snapshot we can find. + $newsyncsnap = getnewestsnapshot($sourcehost,$sourcefs,$sourceisroot); + if ($newsyncsnap eq 0) { + warn "CRITICAL: no snapshots exist on source $sourcefs, and you asked for --no-sync-snap.\n"; + return 0; + } } } my $newsyncsnapescaped = escapeshellparam($newsyncsnap); @@ -223,7 +244,7 @@ sub syncdataset { my $oldestsnapescaped = escapeshellparam($oldestsnap); my $sendcmd = "$sourcesudocmd $zfscmd send $sourcefsescaped\@$oldestsnapescaped"; - my $recvcmd = "$targetsudocmd $zfscmd receive -F $targetfsescaped"; + my $recvcmd = "$targetsudocmd $zfscmd receive $receiveextraargs -F $targetfsescaped"; my $pvsize = getsendsize($sourcehost,"$sourcefs\@$oldestsnap",0,$sourceisroot); my $disp_pvsize = readablebytes($pvsize); @@ -287,6 +308,27 @@ sub syncdataset { # setzfsvalue($targethost,$targetfs,$targetisroot,'readonly',$originaltargetreadonly); } } else { + # resume interrupted receive if there is a valid resume $token + # and because this will ony resume the receive to the next + # snapshot, do a normal sync after that + if (defined($receivetoken)) { + my $sendcmd = "$sourcesudocmd $zfscmd send -t $receivetoken"; + my $recvcmd = "$targetsudocmd $zfscmd receive $receiveextraargs -F $targetfsescaped"; + my $pvsize = getsendsize($sourcehost,"","",$sourceisroot,$receivetoken); + my $disp_pvsize = readablebytes($pvsize); + if ($pvsize == 0) { $disp_pvsize = "UNKNOWN"; } + my $synccmd = buildsynccmd($sendcmd,$recvcmd,$pvsize,$sourceisroot,$targetisroot); + + if (!$quiet) { print "Resuming interrupted zfs send/receive from $sourcefs to $targetfs (~ $disp_pvsize remaining):\n"; } + if ($debug) { print "DEBUG: $synccmd\n"; } + system("$synccmd") == 0 + or die "CRITICAL ERROR: $synccmd failed: $?"; + + # a resumed transfer will only be done to the next snapshot, + # so do an normal sync cycle + return syncdataset($sourcehost, $sourcefs, $targethost, $targetfs); + } + # find most recent matching snapshot and do an -I # to the new snapshot @@ -327,7 +369,7 @@ sub syncdataset { } my $sendcmd = "$sourcesudocmd $zfscmd send $args{'streamarg'} $sourcefsescaped\@$matchingsnapescaped $sourcefsescaped\@$newsyncsnapescaped"; - my $recvcmd = "$targetsudocmd $zfscmd receive -F $targetfsescaped"; + my $recvcmd = "$targetsudocmd $zfscmd receive $receiveextraargs -F $targetfsescaped"; my $pvsize = getsendsize($sourcehost,"$sourcefs\@$matchingsnap","$sourcefs\@$newsyncsnap",$sourceisroot); my $disp_pvsize = readablebytes($pvsize); if ($pvsize == 0) { $disp_pvsize = "UNKNOWN"; } @@ -417,6 +459,8 @@ sub checkcommands { $avail{'localmbuffer'} = 1; $avail{'sourcembuffer'} = 1; $avail{'targetmbuffer'} = 1; + $avail{'sourceresume'} = 1; + $avail{'targetresume'} = 1; return %avail; } @@ -524,6 +568,37 @@ sub checkcommands { $avail{'localpv'} = 1; } + # check for ZFS resume feature support + if ($resume) { + my $resumechkcmd = "$zfscmd get receive_resume_token -d 0"; + + if ($debug) { print "DEBUG: checking availability of zfs resume feature on source...\n"; } + $avail{'sourceresume'} = system("$sourcessh $resumechkcmd >/dev/null 2>&1"); + $avail{'sourceresume'} = $avail{'sourceresume'} == 0 ? 1 : 0; + + if ($debug) { print "DEBUG: checking availability of zfs resume feature on target...\n"; } + $avail{'targetresume'} = system("$targetssh $resumechkcmd >/dev/null 2>&1"); + $avail{'targetresume'} = $avail{'targetresume'} == 0 ? 1 : 0; + + if ($avail{'sourceresume'} == 0 || $avail{'targetresume'} == 0) { + # disable resume + $resume = ''; + + my @hosts = (); + if ($avail{'sourceresume'} == 0) { + push @hosts, 'source'; + } + if ($avail{'targetresume'} == 0) { + push @hosts, 'target'; + } + my $affected = join(" and ", @hosts); + print "WARN: ZFS resume feature not available on $affected machine - sync will continue without resume support.\n"; + } + } else { + $avail{'sourceresume'} = 0; + $avail{'targetresume'} = 0; + } + return %avail; } @@ -932,7 +1007,7 @@ sub getsnaps() { sub getsendsize { - my ($sourcehost,$snap1,$snap2,$isroot) = @_; + my ($sourcehost,$snap1,$snap2,$isroot,$receivetoken) = @_; my $snap1escaped = escapeshellparam($snap1); my $snap2escaped = escapeshellparam($snap2); @@ -958,6 +1033,12 @@ sub getsendsize { $snaps = "$snap1escaped"; } + # in case of a resumed receive, get the remaining + # size based on the resume token + if (defined($receivetoken)) { + $snaps = "-t $receivetoken"; + } + my $getsendsizecmd = "$sourcessh $mysudocmd $zfscmd send -nP $snaps"; if ($debug) { print "DEBUG: getting estimated transfer size from source $sourcehost using \"$getsendsizecmd 2>&1 |\"...\n"; } @@ -970,7 +1051,13 @@ sub getsendsize { # size of proposed xfer in bytes, but we need to remove # human-readable crap from it my $sendsize = pop(@rawsize); - $sendsize =~ s/^size\s*//; + # the output format is different in case of + # a resumed receive + if (defined($receivetoken)) { + $sendsize =~ s/.*\s([0-9]+)$/$1/; + } else { + $sendsize =~ s/^size\s*//; + } chomp $sendsize; # to avoid confusion with a zero size pv, give sendsize @@ -1007,6 +1094,21 @@ sub escapeshellparam { return "'$par'"; } +sub getreceivetoken() { + my ($rhost,$fs,$isroot) = @_; + my $token = getzfsvalue($rhost,$fs,$isroot,"receive_resume_token"); + + if ($token ne '-' && $token ne '') { + return $token; + } + + if ($debug) { + print "DEBUG: no receive token found \n"; + } + + return +} + __END__ =head1 NAME @@ -1044,3 +1146,4 @@ Options: --quiet Suppresses non-error output --dumpsnaps Dumps a list of snapshots during the run --no-command-checks Do not check command existence before attempting transfer. Not recommended + --no-resume Don't use the ZFS resume feature if available