diff --git a/Changelog b/Changelog
index d1e62d90..29d13bb3 100644
--- a/Changelog
+++ b/Changelog
@@ -2,8 +2,10 @@ Changelog for Percona Toolkit
 
 v3.0.7 
 
- * Feature      PT-644 : Added --mysql-only option to pt-stalk for RDS
+ * Fixed Bug    PT-244 : pt-online-schema-change --data-dir option broken for partitioned table
+ * Feature      PT-633 : Added --mysql-only option to pt-stalk for RDS
  * Fixed bug    PT-1256: pt-table-sync does not use the character set for the table it is synchronizing
+ * Fixed bug    PT-1455: pt-osc is stuck when the table that is being altered is filtered out in the slave
  * Fixed bug   PMM-1905: Explain fails if encounters negative "ntoreturn"
 
 v3.0.6 released 2017-12-20
diff --git a/bin/pt-archiver b/bin/pt-archiver
index d08e95ed..b297def3 100755
--- a/bin/pt-archiver
+++ b/bin/pt-archiver
@@ -5373,15 +5373,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -5598,6 +5599,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -5634,7 +5675,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-config-diff b/bin/pt-config-diff
index 7a340806..35b0134f 100755
--- a/bin/pt-config-diff
+++ b/bin/pt-config-diff
@@ -4711,15 +4711,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4936,6 +4937,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4972,7 +5013,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-deadlock-logger b/bin/pt-deadlock-logger
index d2b09b78..4ed24bb3 100755
--- a/bin/pt-deadlock-logger
+++ b/bin/pt-deadlock-logger
@@ -3775,15 +3775,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4000,6 +4001,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4036,7 +4077,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-diskstats b/bin/pt-diskstats
index 9773fd84..a1bb8252 100755
--- a/bin/pt-diskstats
+++ b/bin/pt-diskstats
@@ -4328,15 +4328,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4553,6 +4554,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4589,7 +4630,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-duplicate-key-checker b/bin/pt-duplicate-key-checker
index d6586855..9cca3223 100755
--- a/bin/pt-duplicate-key-checker
+++ b/bin/pt-duplicate-key-checker
@@ -4379,15 +4379,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4604,6 +4605,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4640,7 +4681,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-find b/bin/pt-find
index c1e4a940..e63870c9 100755
--- a/bin/pt-find
+++ b/bin/pt-find
@@ -3093,15 +3093,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -3318,6 +3319,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -3354,7 +3395,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-fk-error-logger b/bin/pt-fk-error-logger
index 8ce7b713..e99aae70 100755
--- a/bin/pt-fk-error-logger
+++ b/bin/pt-fk-error-logger
@@ -3280,15 +3280,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -3505,6 +3506,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -3541,7 +3582,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-heartbeat b/bin/pt-heartbeat
index b3be48c7..f0566be2 100755
--- a/bin/pt-heartbeat
+++ b/bin/pt-heartbeat
@@ -4980,15 +4980,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -5205,6 +5206,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -5241,7 +5282,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-index-usage b/bin/pt-index-usage
index 75239c1f..d34f34a4 100755
--- a/bin/pt-index-usage
+++ b/bin/pt-index-usage
@@ -5777,15 +5777,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -6002,6 +6003,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -6038,7 +6079,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-kill b/bin/pt-kill
index 01154183..5e1fd437 100755
--- a/bin/pt-kill
+++ b/bin/pt-kill
@@ -6185,15 +6185,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -6410,6 +6411,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -6446,7 +6487,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-online-schema-change b/bin/pt-online-schema-change
index 91184b0d..b7c7c64b 100755
--- a/bin/pt-online-schema-change
+++ b/bin/pt-online-schema-change
@@ -4281,7 +4281,8 @@ sub recurse_to_slaves {
       PTDEBUG && _d('Connected to', $dp->as_string($slave_dsn));
    };
    if ( $EVAL_ERROR ) {
-      print STDERR "Cannot connect to ", $dp->as_string($slave_dsn), "\n"
+      #TODO REMOVE DEBUG
+      print STDERR "1> Cannot connect to ", $dp->as_string($slave_dsn), "\n"
          or die "Cannot print: $OS_ERROR";
       return;
    }
@@ -5001,7 +5002,7 @@ sub wait {
          my $lag = $get_lag->($lagged_slaves[$i]->{cxn});
          PTDEBUG && _d($lagged_slaves[$i]->{cxn}->name(),
             'slave lag:', $lag);
-         if ( !defined $lag || $lag > $max_lag ) {
+        if ( defined $lag && $lag > $max_lag ) {
             $lagged_slaves[$i]->{lag} = $lag;
          }
          else {
@@ -7413,15 +7414,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -7638,6 +7640,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -7674,7 +7716,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
@@ -8693,7 +8735,8 @@ sub main {
                   # to stop lagging.  If any replica is stopped, the tool
                   # waits forever until the replica is started."
                   # https://bugs.launchpad.net/percona-toolkit/+bug/1402051
-                  PTDEBUG && _d('Cannot connect to', $cxn->name(), ':',
+                  #TODO REMOVE DEBUG
+                  PTDEBUG && _d('2> Cannot connect to', $cxn->name(), ':',
                      $EVAL_ERROR);
                   # Make ReplicaLagWaiter::wait() report slave is stopped.
                   return undef; 
@@ -9134,7 +9177,8 @@ sub main {
       }
    };
 
-   if ( $slaves && scalar @$slaves ) {
+   my $table_is_replicated;
+   if ( $slaves && scalar @$slaves && $table_is_replicated) {
       foreach my $slave (@$slaves) {
          my ($pr, $pr_first_report);
          if ( $o->get('progress') ) {
@@ -12843,7 +12887,7 @@ Default character set.
 
 =item * D
 
-dsn: database; copy: yes
+dsn: database; copy: no
 
 Database for the old and new table.
 
@@ -12994,6 +13038,6 @@ Place, Suite 330, Boston, MA  02111-1307  USA.
 
 =head1 VERSION
 
-pt-online-schema-change 3.0.6
+pt-online-schema-change 3.0.7
 
 =cut
diff --git a/bin/pt-query-digest b/bin/pt-query-digest
index ba90a55f..4923c3cb 100755
--- a/bin/pt-query-digest
+++ b/bin/pt-query-digest
@@ -12446,15 +12446,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -12671,6 +12672,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -12707,7 +12748,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-slave-delay b/bin/pt-slave-delay
index e79bd633..0ff73c59 100755
--- a/bin/pt-slave-delay
+++ b/bin/pt-slave-delay
@@ -3597,15 +3597,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -3822,6 +3823,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -3858,7 +3899,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-slave-restart b/bin/pt-slave-restart
index f202ff2a..59cd6315 100755
--- a/bin/pt-slave-restart
+++ b/bin/pt-slave-restart
@@ -4306,15 +4306,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4531,6 +4532,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4567,7 +4608,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-table-checksum b/bin/pt-table-checksum
index c1f14786..67d4fccc 100755
--- a/bin/pt-table-checksum
+++ b/bin/pt-table-checksum
@@ -797,15 +797,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -1022,6 +1023,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -1058,7 +1099,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-table-sync b/bin/pt-table-sync
index 93c06865..0817e384 100755
--- a/bin/pt-table-sync
+++ b/bin/pt-table-sync
@@ -9215,15 +9215,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -9440,6 +9441,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -9476,7 +9517,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-upgrade b/bin/pt-upgrade
index c4753636..4e671878 100755
--- a/bin/pt-upgrade
+++ b/bin/pt-upgrade
@@ -4086,15 +4086,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4311,6 +4312,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4347,7 +4388,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/bin/pt-variable-advisor b/bin/pt-variable-advisor
index ce80e9f2..e3aeb29e 100755
--- a/bin/pt-variable-advisor
+++ b/bin/pt-variable-advisor
@@ -4504,15 +4504,16 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -4729,6 +4730,46 @@ sub get_instance_id {
 }
 
 
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
+
 sub pingback {
    my (%args) = @_;
    my @required_args = qw(url instances);
@@ -4765,7 +4806,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/config/deb/postinst b/config/deb/postinst
new file mode 100644
index 00000000..836c6c91
--- /dev/null
+++ b/config/deb/postinst
@@ -0,0 +1,8 @@
+#!/bin/bash
+
+if [ ! -e /etc/percona-toolkit/.percona.toolkit.uuid ]; then
+  mkdir -p /etc/percona-toolkit
+  perl -e 'printf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;' > /etc/percona-toolkit/.percona.toolkit.uuid
+fi
+
+#DEBHELPER#
diff --git a/config/rpm/percona-toolkit.spec b/config/rpm/percona-toolkit.spec
index b2bddfc9..e19a673c 100644
--- a/config/rpm/percona-toolkit.spec
+++ b/config/rpm/percona-toolkit.spec
@@ -42,6 +42,11 @@ find $RPM_BUILD_ROOT -type f -name 'percona-toolkit.pod' -exec rm -f {} ';'
 rm -rf $RPM_BUILD_ROOT/usr/share/perl5
 chmod -R u+w $RPM_BUILD_ROOT/*
 
+%post
+if [ ! -e /etc/percona-toolkit/.percona.toolkit.uuid ]; then
+  mkdir -p /etc/percona-toolkit
+  perl -e 'printf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;' > /etc/percona-toolkit/.percona.toolkit.uuid
+fi
 
 %clean
 rm -rf $RPM_BUILD_ROOT
diff --git a/lib/VersionCheck.pm b/lib/VersionCheck.pm
index 0c126d11..b612dd04 100644
--- a/lib/VersionCheck.pm
+++ b/lib/VersionCheck.pm
@@ -48,6 +48,14 @@ eval {
    require HTTP::Micro;
 };
 
+my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
+my @vc_dirs = (
+   '/etc/percona',
+   '/etc/percona-toolkit',
+   '/tmp',
+   "$home",
+);
+
 # Return the version check file used to keep track of
 # MySQL instance that have been checked and when.  Some
 # systems use random tmp dirs; we don't want that else
@@ -55,13 +63,6 @@ eval {
 # per system is the goal, so prefer global sys dirs first.
 {
    my $file    = 'percona-version-check';
-   my $home    = $ENV{HOME} || $ENV{HOMEPATH} || $ENV{USERPROFILE} || '.';
-   my @vc_dirs = (
-      '/etc/percona',
-      '/etc/percona-toolkit',
-      '/tmp',
-      "$home",
-   );
 
    sub version_check_file {
       foreach my $dir ( @vc_dirs ) {
@@ -326,6 +327,49 @@ sub get_instance_id {
    return $name, $id;
 }
 
+
+# This function has been implemented solely to be able to count individual 
+# Toolkit users for statistics. It uses a random UUID, no client info is
+# being gathered nor stored
+sub get_uuid {
+    my $uuid_file = '/.percona-toolkit.uuid';
+    foreach my $dir (@vc_dirs) {
+        my $filename = $dir.$uuid_file;
+        my $uuid=_read_uuid($filename);
+        return $uuid if $uuid;
+    }
+
+    my $filename = $ENV{"HOME"} . $uuid_file;
+    my $uuid = _generate_uuid();
+
+    open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";
+    print $fh $uuid;
+    close $fh;
+
+    return $uuid;
+}   
+
+sub _generate_uuid {
+    return sprintf+($}="%04x")."$}-$}-$}-$}-".$}x3,map rand 65537,0..7;
+}
+
+sub _read_uuid {
+    my $filename = shift;
+    my $fh;
+
+    eval {
+        open($fh, '<:encoding(UTF-8)', $filename);
+    };
+    return if ($EVAL_ERROR);
+
+    my $uuid;
+    eval { $uuid = <$fh>; };
+    return if ($EVAL_ERROR);
+
+    chomp $uuid;
+    return $uuid;
+}
+
 # #############################################################################
 # Protocol handlers
 # #############################################################################
@@ -387,7 +431,7 @@ sub pingback {
    my $client_content = encode_client_response(
       items      => $items,
       versions   => $versions,
-      general_id => md5_hex( hostname() ),
+      general_id => get_uuid(),
    );
 
    my $client_response = {
diff --git a/t/lib/VersionCheck.t b/t/lib/VersionCheck.t
index ba9881a5..30436a68 100644
--- a/t/lib/VersionCheck.t
+++ b/t/lib/VersionCheck.t
@@ -201,7 +201,7 @@ is_deeply(
 # Former Pingback tests
 # #############################################################################
 
-my $general_id = md5_hex( hostname() );
+my $general_id = VersionCheck::get_uuid();
 my $master_id;  # the instance ID, _not_ 12345 etc.
 my $slave1_id;  # the instance ID, _not_ 12346 etc.
 my ($mysql_ver, $mysql_distro);
@@ -679,6 +679,22 @@ foreach my $tool ( @vc_tools ) {
    );
 }
 
+my $should_remove_uuid_file;
+my $home_uuid_file = $ENV{"HOME"} . "/.percona-toolkit.uuid";
+
+if ( ! -e $home_uuid_file ) {
+    $should_remove_uuid_file = 1;
+}
+
+my $uuid = VersionCheck::get_uuid();
+is (
+    length($uuid),
+    36,
+    "Have a valid UUID4",
+);
+
+unlink $home_uuid_file if $should_remove_uuid_file;
+
 # #############################################################################
 # Done.
 # #############################################################################
diff --git a/t/pt-online-schema-change/alter_active_table.t b/t/pt-online-schema-change/alter_active_table.t
index b3c42a20..f5fe7e43 100644
--- a/t/pt-online-schema-change/alter_active_table.t
+++ b/t/pt-online-schema-change/alter_active_table.t
@@ -165,7 +165,7 @@ else {
 }
 $master_dbh->do("USE pt_osc");
 $master_dbh->do("TRUNCATE TABLE t");
-$master_dbh->do("LOAD DATA LOCAL INFILE '$trunk/t/pt-online-schema-change/samples/basic_no_fks.data' INTO TABLE t");
+$master_dbh->do("LOAD DATA INFILE '$trunk/t/pt-online-schema-change/samples/basic_no_fks.data' INTO TABLE t");
 $master_dbh->do("ANALYZE TABLE t");
 $sb->wait_for_slaves();
 
@@ -215,7 +215,7 @@ is(
 
 $master_dbh->do("USE pt_osc");
 $master_dbh->do("TRUNCATE TABLE t");
-$master_dbh->do("LOAD DATA LOCAL INFILE '$trunk/t/pt-online-schema-change/samples/basic_no_fks.data' INTO TABLE t");
+$master_dbh->do("LOAD DATA INFILE '$trunk/t/pt-online-schema-change/samples/basic_no_fks.data' INTO TABLE t");
 $master_dbh->do("ANALYZE TABLE t");
 $sb->wait_for_slaves();
 
diff --git a/t/pt-online-schema-change/issue-1646713.t b/t/pt-online-schema-change/issue-1646713.t
index 3d716db8..10e529f5 100644
--- a/t/pt-online-schema-change/issue-1646713.t
+++ b/t/pt-online-schema-change/issue-1646713.t
@@ -46,6 +46,11 @@ my $exit_status;
 my $sample  = "t/pt-online-schema-change/samples/";
 
 $sb->load_file('master', "$sample/issue-1646713.sql");
+my $num_rows = 1000;
+my $master_port = 12345;
+
+$master_dbh->do("FLUSH TABLES");
+$sb->wait_for_slaves();
 
 sub start_thread {
    my ($dsn_opts, $sleep_time) = @_;
@@ -53,14 +58,18 @@ sub start_thread {
    my $sb = new Sandbox(basedir => '/tmp', DSNParser => $dp);
    my $dbh = $sb->get_dbh_for('master');
    diag("Thread started: Sleeping $sleep_time seconds before updating the PK field for row with id=1 in test.sbtest");
-   sleep($sleep_time);
+   # We need to lock the tables to prevent osc to really start before we are able to write the row to the table
+   $dbh->do("LOCK TABLES `test`.`o1` WRITE");
+   select(undef, undef, undef, $sleep_time);
    $dbh->do("UPDATE `test`.`o1` SET id=0 WHERE id=1");
+   $dbh->do("UNLOCK TABLES");
    diag("Row updated");
 }
-my $thr = threads->create('start_thread', $dsn_opts, 1);
+my $thr = threads->create('start_thread', $dsn_opts, 0.50);
 $thr->detach();
 threads->yield();
 
+
 diag("Starting osc. A row will be updated in a different thread.");
 my $dir = tempdir( CLEANUP => 1 );
 $output = output(
@@ -71,6 +80,7 @@ $output = output(
          ),
       },
 );
+diag($output);
 
 like(
       $output,
diff --git a/t/pt-online-schema-change/pt-1455.t b/t/pt-online-schema-change/pt-1455.t
new file mode 100644
index 00000000..3861019d
--- /dev/null
+++ b/t/pt-online-schema-change/pt-1455.t
@@ -0,0 +1,94 @@
+#!/usr/bin/env perl
+
+BEGIN {
+    die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
+    unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
+    unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
+};
+
+use strict;
+use warnings FATAL => 'all';
+use threads;
+use threads::shared;
+use Thread::Semaphore;
+
+use English qw(-no_match_vars);
+use Test::More;
+
+use Data::Dumper;
+use PerconaTest;
+use Sandbox;
+use SqlModes;
+use File::Temp qw/ tempdir /;
+
+plan tests => 3;
+
+require "$trunk/bin/pt-online-schema-change";
+
+my $dp = new DSNParser(opts=>$dsn_opts);
+my $sb = new Sandbox(basedir => '/tmp', DSNParser => $dp);
+
+my $master_dbh = $sb->get_dbh_for("master");
+my $master_dsn = $sb->dsn_for("master");
+
+my $slave1_dbh = $sb->get_dbh_for("slave1");
+my $slave1_dsn = $sb->dsn_for("slave1");
+
+# The sandbox servers run with lock_wait_timeout=3 and it's not dynamic
+# so we need to specify --set-vars innodb_lock_wait_timeout=3 else the
+# tool will die.
+my @args = (qw(--set-vars innodb_lock_wait_timeout=3));
+my $output;
+my $exit_status;
+
+diag("Setting replication filters on slave 2");
+$sb->load_file('slave2', "t/pt-online-schema-change/samples/pt-1455_slave.sql");
+diag("Setting replication filters on slave 1");
+$sb->load_file('slave1', "t/pt-online-schema-change/samples/pt-1455_slave.sql");
+diag("Setting replication filters on master");
+$sb->load_file('master', "t/pt-online-schema-change/samples/pt-1455_master.sql",undef, no_wait => 1);
+diag("replication filters set");
+
+my $num_rows = 1000;
+my $master_port = 12345;
+
+diag("Loading $num_rows into the table. This might take some time.");
+diag(`util/mysql_random_data_load_linux_amd64 --host=127.1 --port=$master_port --user=msandbox --password=msandbox employees t1 $num_rows`);
+diag("$num_rows rows loaded. Starting tests.");
+
+$master_dbh->do("FLUSH TABLES");
+
+($output, $exit_status) = full_output(
+    sub { pt_online_schema_change::main(@args, "$master_dsn,D=employees,t=t1",
+            '--execute', '--no-check-replication-filters', 
+            '--alter', "engine=innodb",
+        ),
+    },
+    stderr => 1,
+);
+
+is(
+    $exit_status,
+    0,
+    "PT-1455 Successfully altered. Exit status = 0",
+);
+
+like(
+    $output,
+    qr/Successfully altered/s,
+    "PT-1455 Got successfully altered message.",
+);
+
+$master_dbh->do("DROP DATABASE IF EXISTS employees");
+
+diag("Resetting replication filters on slave 2");
+$sb->load_file('slave2', "t/pt-online-schema-change/samples/pt-1455_reset_slave.sql");
+diag("Resetting replication filters on slave 1");
+$sb->load_file('slave1', "t/pt-online-schema-change/samples/pt-1455_reset_slave.sql");
+
+# #############################################################################
+# Done.
+# #############################################################################
+$sb->wipe_clean($master_dbh);
+ok($sb->ok(), "Sandbox servers") or BAIL_OUT(__FILE__ . " broke the sandbox");
+done_testing;
diff --git a/t/pt-online-schema-change/samples/issue-1646713.sql b/t/pt-online-schema-change/samples/issue-1646713.sql
index e4ac06e0..5f44e4e7 100644
--- a/t/pt-online-schema-change/samples/issue-1646713.sql
+++ b/t/pt-online-schema-change/samples/issue-1646713.sql
@@ -2,40 +2,12 @@ DROP DATABASE IF EXISTS `test`;
 CREATE DATABASE IF NOT EXISTS `test`;
 USE test;
 
--- MySQL dump 10.13  Distrib 5.7.14-8, for debian-linux-gnu (x86_64)
---
--- Host: localhost    Database: test
--- ------------------------------------------------------
--- Server version	5.7.14-8-log
-
-/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
-/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
-/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
-/*!40101 SET NAMES utf8 */;
-/*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */;
-/*!40103 SET TIME_ZONE='+00:00' */;
-/*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */;
-/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
-/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
-/*!40111 SET @OLD_SQL_NOTES=@@SQL_NOTES, SQL_NOTES=0 */;
-
---
--- Table structure for table `sbtest`
---
-
 DROP TABLE IF EXISTS `o1`;
-/*!40101 SET @saved_cs_client     = @@character_set_client */;
-/*!40101 SET character_set_client = utf8 */;
 CREATE TABLE `o1` (
-  `id` int
-(10) unsigned NOT NULL AUTO_INCREMENT,
+  `id` int (10) unsigned NOT NULL AUTO_INCREMENT,
   PRIMARY KEY (`id`)
-) ENGINE=InnoDB AUTO_INCREMENT=1100001 DEFAULT CHARSET=latin1;
-/*!40101 SET character_set_client = @saved_cs_client */;
+) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=latin1;
 
---
--- Dumping data for table `sbtest`
---
 
 LOCK TABLES `o1` WRITE;
 /*!40000 ALTER TABLE `o1` DISABLE KEYS */;
@@ -140,16 +112,4 @@ INSERT INTO `o1` VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),
 (980),(981),(982),(983),(984),(985),(986),(987),(988),(989),
 (990),(991),(992),(993),(994),(995),(996),(997),(998),(999),
 (10000);
-/*!40000 ALTER TABLE `o1` ENABLE KEYS */;
 UNLOCK TABLES;
-/*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */;
-
-/*!40101 SET SQL_MODE=@OLD_SQL_MODE */;
-/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
-/*!40014 SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS */;
-/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
-/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
-/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
-/*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
-
--- Dump completed on 2017-03-14 15:19:26
diff --git a/t/pt-online-schema-change/samples/pt-1455_master.sql b/t/pt-online-schema-change/samples/pt-1455_master.sql
new file mode 100644
index 00000000..fd6bed3a
--- /dev/null
+++ b/t/pt-online-schema-change/samples/pt-1455_master.sql
@@ -0,0 +1,8 @@
+DROP DATABASE IF EXISTS employees;
+CREATE DATABASE employees;
+-- This table should be replicated
+CREATE TABLE employees.t1 (
+    id INT AUTO_INCREMENT PRIMARY KEY, 
+    f2 INT
+) ENGINE=InnoDB;
+
diff --git a/t/pt-online-schema-change/samples/pt-1455_reset_slave.sql b/t/pt-online-schema-change/samples/pt-1455_reset_slave.sql
new file mode 100644
index 00000000..59c207b0
--- /dev/null
+++ b/t/pt-online-schema-change/samples/pt-1455_reset_slave.sql
@@ -0,0 +1,6 @@
+STOP SLAVE;
+CHANGE REPLICATION FILTER REPLICATE_IGNORE_DB = ();
+CHANGE REPLICATION FILTER REPLICATE_IGNORE_TABLE = ();
+CHANGE REPLICATION FILTER REPLICATE_WILD_IGNORE_TABLE = ();
+RESET SLAVE;
+START SLAVE;
diff --git a/t/pt-online-schema-change/samples/pt-1455_slave.sql b/t/pt-online-schema-change/samples/pt-1455_slave.sql
new file mode 100644
index 00000000..86ee176a
--- /dev/null
+++ b/t/pt-online-schema-change/samples/pt-1455_slave.sql
@@ -0,0 +1,6 @@
+STOP SLAVE;
+CHANGE REPLICATION FILTER REPLICATE_IGNORE_DB = (`ignored_db`);
+CHANGE REPLICATION FILTER REPLICATE_IGNORE_TABLE = (`idb1`.`it1`, `idb1`.`it2`);
+CHANGE REPLICATION FILTER REPLICATE_WILD_IGNORE_TABLE = ('employees.eit%');
+RESET SLAVE;
+START SLAVE;