mirror of https://github.com/schoebel/mars
marsadm: rewrite / correct symlink faking
This commit is contained in:
Thomas Schoebel-Theuer
parent
03f418c2c7
commit
22f75b9d71
|
|
@ -471,49 +471,105 @@ sub _get_ip {
|
|||
return undef;
|
||||
}
|
||||
|
||||
# Which primary was active in the past when logfile number $log_nr was created?
|
||||
# In general, this may be even a node which doesn't exist anymore.
|
||||
# $supposed_primary should be normally empty, but may be used
|
||||
# to give a hint and check for consistency of ancient knowledge.
|
||||
|
||||
sub _get_former_primary {
|
||||
my ($basedir, $log_nr, $supposed_primary) = @_;
|
||||
my $primary = $supposed_primary;
|
||||
foreach my $type ("log", "version") {
|
||||
my $base_path = sprintf("$basedir/$type-%09d-", $log_nr);
|
||||
my $pri_path = "$base_path$supposed_primary";
|
||||
my $log_path = "$base_path*";
|
||||
my @names = glob($log_path);
|
||||
if (!@names) {
|
||||
if ($type eq "log" and !$supposed_primary) {
|
||||
next;
|
||||
}
|
||||
ldie "Sorry, there exist no names '$log_path'\n" unless $supposed_primary;
|
||||
} elsif (scalar(@names) == 1) {
|
||||
my $found = $names[0];
|
||||
if ($supposed_primary) {
|
||||
ldie "Sorry, '$pri_path' does not exist, although '$found' would exist.\n" unless $pri_path eq $found;
|
||||
} else { # assume that the found name is the right one.
|
||||
$pri_path = $found;
|
||||
lprint "found '$pri_path'\n";
|
||||
ldie "found name is malformed\n" unless $pri_path =~ m:^$base_path(.*):;
|
||||
$primary = $1;
|
||||
}
|
||||
} else { # multiple exist...
|
||||
lprint "There are multiple names with number $log_nr.\n";
|
||||
my $present = 0;
|
||||
foreach my $file (@names) {
|
||||
lprint " $file\n";
|
||||
$present++ if $file eq $pri_path;
|
||||
}
|
||||
if ($type eq "log") {
|
||||
lwarn "Usually, this is an indication for split-brain.\n";
|
||||
lwarn "Be careful!\n";
|
||||
}
|
||||
ldie "Cannot select between them -- no primary preference given.\n" unless $supposed_primary;
|
||||
ldie "Sorry, '$pri_path' is not among them.\n" unless $present;
|
||||
lprint "=> using '$pri_path' out of them\n";
|
||||
}
|
||||
return $primary;
|
||||
}
|
||||
ldie "could not determine old primary site for logfile version number $log_nr\n";
|
||||
}
|
||||
|
||||
sub _fake_versionlink {
|
||||
my ($basedir, $prev, $primary) = @_;
|
||||
$prev =~ s/^log-([0-9]+)-.*$/$1/;
|
||||
$prev--;
|
||||
if ($prev > 0) {
|
||||
my $prevversion = sprintf("$basedir/version-%09d-$primary", $prev);
|
||||
my $prevlink = get_link($prevversion);
|
||||
if (!$prevlink) { # try any one else
|
||||
$prevversion = sprintf("$basedir/version-%09d-*", $prev);
|
||||
my @test = glob($prevversion);
|
||||
$prevlink = shift @test;
|
||||
}
|
||||
if ($prevlink) {
|
||||
lprint "creating faked version symlink...\n";
|
||||
my $myversion = sprintf("$basedir/version-%09d-$host", $prev);
|
||||
system("rm -f $myversion.tmp");
|
||||
symlink($prevlink, "$myversion.tmp") or ldie "cannot create faked version symlink '$myversion'\n";
|
||||
system("mv $myversion.tmp $myversion");
|
||||
} else {
|
||||
lwarn "cannot read symlink '$prevversion' -- cannot create fake\n";
|
||||
my ($basedir, $log_nr, $primary) = @_;
|
||||
$primary = _get_former_primary(@_) unless $primary;
|
||||
my $new_version = sprintf("$basedir/version-%09d-$host", $log_nr);
|
||||
my $pri_version = sprintf("$basedir/version-%09d-$primary", $log_nr);
|
||||
if ($primary eq $host) {
|
||||
lwarn "it makes no sense to fake my own version link '$new_version'\n";
|
||||
return;
|
||||
}
|
||||
my $pri_link = get_link($pri_version);
|
||||
if (!$pri_link) { # try any one else
|
||||
lwarn "cannot read symlink '$pri_version' -- trying a neighbor link instead\n";
|
||||
my $try_version = sprintf("$basedir/version-%09d-*", $log_nr);
|
||||
my @test = glob($try_version);
|
||||
my $test_version = shift @test;
|
||||
if ($test_version) {
|
||||
lwarn "trying substitute symlink '$test_version'\n";
|
||||
my $test_link = get_link($test_version);
|
||||
if ($test_link) {
|
||||
$pri_link = $test_link;
|
||||
lwarn "got value '$pri_link', hopefully this is right\n" if $pri_link;
|
||||
}
|
||||
}
|
||||
}
|
||||
if ($pri_link) {
|
||||
lprint "creating new version symlink '$new_version' -> '$pri_link'\n";
|
||||
system("rm -f $new_version.tmp");
|
||||
symlink($pri_link, "$new_version.tmp") or ldie "cannot create faked version symlink '$new_version'\n";
|
||||
system("mv $new_version.tmp $new_version");
|
||||
} else {
|
||||
lwarn "cannot read symlink '$pri_version' -- cannot create faked versionlink '$pri_version'\n";
|
||||
}
|
||||
}
|
||||
|
||||
sub _set_replaylink {
|
||||
my ($basedir, $replay, $primary) = @_;
|
||||
my $replaylink = "$basedir/replay-$host";
|
||||
my $oldreplay = get_link($replaylink);
|
||||
# fake old version symlink when necessary
|
||||
if ($oldreplay) {
|
||||
my $oldbase = $oldreplay;
|
||||
my $base = $replay;
|
||||
$oldbase =~ s/^([^,]+).*/$1/;
|
||||
$base =~ s/^([^,]+).*/$1/;
|
||||
if ($base ne $oldbase) {
|
||||
_fake_versionlink($basedir, $oldreplay, $primary);
|
||||
}
|
||||
my ($basedir, $log_nr) = @_;
|
||||
my $primary = _get_former_primary(@_);
|
||||
my $rep_path = "$basedir/replay-$host";
|
||||
my $rep_val = sprintf("log-%09d-$primary,0,0", $log_nr);
|
||||
lprint "creating new replaylink '$rep_path' -> '$rep_val'\n";
|
||||
system("rm -f $rep_path.tmp");
|
||||
symlink($rep_val, "$rep_path.tmp") or ldie "cannot create symlink '$rep_path'\n";
|
||||
system("mv $rep_path.tmp $rep_path");
|
||||
|
||||
if ($log_nr > 1) {
|
||||
my $old_primary = "";
|
||||
my $vers_link = sprintf("$basedir/version-%09d-$primary", $log_nr);
|
||||
my $vers_val = get_link($vers_link);
|
||||
$old_primary = $1 if $vers_val =~ m/:.*,log-[0-9]+-([^,]+),/;
|
||||
_fake_versionlink($basedir, $log_nr - 1, $old_primary);
|
||||
}
|
||||
# copy pervious version symlink
|
||||
_fake_versionlink($basedir, $replay, $primary);
|
||||
# create replay symlink
|
||||
symlink($replay, "$replaylink.tmp") or ldie "cannot create replay status\n";
|
||||
system("mv $replaylink.tmp $replaylink");
|
||||
}
|
||||
|
||||
##################################################################
|
||||
|
|
@ -622,7 +678,7 @@ sub create_res {
|
|||
|
||||
my $tmp = "$mars/.tmp.$res";
|
||||
my $primary;
|
||||
my $replay;
|
||||
my $replay_nr = -1;
|
||||
if ($create) {
|
||||
_create_cluster(@_);
|
||||
system("rm -rf $tmp");
|
||||
|
|
@ -647,8 +703,12 @@ sub create_res {
|
|||
$size = $oldsize;
|
||||
}
|
||||
ldie "sizes differ: real size = $oldsize, but requested size = $size\n" unless $oldsize == $size;
|
||||
$replay = get_link("$tmp/replay-$primary");
|
||||
$replay =~ s/,[0-9]+,[0-9]+$/,0,0/;
|
||||
my $replay = get_link("$tmp/replay-$primary");
|
||||
if ($replay =~ m/^log-([0-9]+)-/) {
|
||||
$replay_nr = $1;
|
||||
} else {
|
||||
ldie "cannot determine current logfile number.\n";
|
||||
}
|
||||
}
|
||||
|
||||
my $file = "$tmp/data-$host";
|
||||
|
|
@ -691,7 +751,7 @@ sub create_res {
|
|||
rename($tmp, "$mars/resource-$res") or ldie "cannot finalize resource '$res'\n";
|
||||
lprint "successfully created resource '$res'\n";
|
||||
} else {
|
||||
_set_replaylink($tmp, $replay, $primary);
|
||||
_set_replaylink($tmp, $replay_nr, $primary);
|
||||
symlink("0", "$tmp/syncstatus-$host") or ldie "cannot start initial sync\n";
|
||||
system("rm -f $tmp/connect-$host");
|
||||
symlink($primary, "$tmp/connect-$host") or ldie "cannot create peer connect symlink\n";
|
||||
|
|
@ -945,8 +1005,9 @@ sub invalidate_res {
|
|||
symlink("0", $dst) or ldie "cannot create invalidation symlink '$dst'\n";
|
||||
my $primary = _get_designated_primary($res);
|
||||
my $replay = get_link("$mars/resource-$res/replay-$primary");
|
||||
$replay =~ s/,[0-9]+,[0-9]+$/,0,0/;
|
||||
_set_replaylink("$mars/resource-$res", $replay, $primary);
|
||||
$replay =~ m/^log-([0-9]+)-/ or ldie "replay link '$replay' is not parsable\n";
|
||||
my $replay_nr = $1;
|
||||
_set_replaylink("$mars/resource-$res", $replay_nr, $primary);
|
||||
if ($was_on) {
|
||||
_trigger();
|
||||
lprint "waiting...\n";
|
||||
|
|
|
|||
Loading…
Reference in New Issue