diff --git a/btrbk b/btrbk
index 9848756..bca525f 100755
--- a/btrbk
+++ b/btrbk
@@ -104,20 +104,20 @@ my %config_options = (
 
   # deprecated options
   snapshot_preserve_daily     => { default => 'all', accept => [ "all" ], accept_numeric => 1, context => [ "root", "volume", "subvolume" ],
-                                   deprecated => { DEFAULT => { ABORT => 1, warn => 'Please use "snapshot_preserve" and/or "snapshot_preserve_min"' } } },
+                                   deprecated => { DEFAULT => { FAILSAFE_PRESERVE => 1, warn => 'Please use "snapshot_preserve" and/or "snapshot_preserve_min"' } } },
   snapshot_preserve_weekly    => { default => 0, accept => [ "all" ], accept_numeric => 1, context => [ "root", "volume", "subvolume" ],
-                                   deprecated => { DEFAULT => { ABORT => 1, warn => 'Please use "snapshot_preserve" and/or "snapshot_preserve_min"' } } },
+                                   deprecated => { DEFAULT => { FAILSAFE_PRESERVE => 1, warn => 'Please use "snapshot_preserve" and/or "snapshot_preserve_min"' } } },
   snapshot_preserve_monthly   => { default => 'all', accept => [ "all" ], accept_numeric => 1, context => [ "root", "volume", "subvolume" ],
-                                   deprecated => { DEFAULT => { ABORT => 1, warn => 'Please use "snapshot_preserve" and/or "snapshot_preserve_min"' } } },
+                                   deprecated => { DEFAULT => { FAILSAFE_PRESERVE => 1, warn => 'Please use "snapshot_preserve" and/or "snapshot_preserve_min"' } } },
   target_preserve_daily       => { default => 'all', accept => [ "all" ], accept_numeric => 1,
-                                   deprecated => { DEFAULT => { ABORT => 1, warn => 'Please use "target_preserve" and/or "target_preserve_min"' } } },
+                                   deprecated => { DEFAULT => { FAILSAFE_PRESERVE => 1, warn => 'Please use "target_preserve" and/or "target_preserve_min"' } } },
   target_preserve_weekly      => { default => 0, accept => [ "all" ], accept_numeric => 1,
-                                   deprecated => { DEFAULT => { ABORT => 1, warn => 'Please use "target_preserve" and/or "target_preserve_min"' } } },
+                                   deprecated => { DEFAULT => { FAILSAFE_PRESERVE => 1, warn => 'Please use "target_preserve" and/or "target_preserve_min"' } } },
   target_preserve_monthly     => { default => 'all', accept => [ "all" ], accept_numeric => 1,
-                                   deprecated => { DEFAULT => { ABORT => 1, warn => 'Please use "target_preserve" and/or "target_preserve_min"' } } },
+                                   deprecated => { DEFAULT => { FAILSAFE_PRESERVE => 1, warn => 'Please use "target_preserve" and/or "target_preserve_min"' } } },
   resume_missing              => { default => "yes", accept => [ "yes", "no" ],
                                    deprecated => { yes => { warn => 'ignoring (missing backups are always resumed since btrbk v0.23.0)' },
-                                                   no  => { ABORT => 1, warn => 'Please use "target_preserve_min latest" and "target_preserve no" if you want to keep only the latest backup', } } },
+                                                   no  => { FAILSAFE_PRESERVE => 1, warn => 'Please use "target_preserve_min latest" and "target_preserve no" if you want to keep only the latest backup', } } },
   snapshot_create_always      => { default => undef, accept => [ "yes", "no" ],
                                    deprecated => { yes => { warn => "Please use \"snapshot_create always\"",
                                                             replace_key   => "snapshot_create",
@@ -2244,12 +2244,24 @@ sub append_config_option($$$$;$)
   }
 
   if($opt->{deprecated}) {
-    WARN "Found deprecated option \"$key $value\"" . $config_file_statement . ": " .
-           ($opt->{deprecated}->{$value}->{warn} // $opt->{deprecated}->{DEFAULT}->{warn});
+    if(my $warn_msg = ($opt->{deprecated}->{$value}->{warn} || $opt->{deprecated}->{DEFAULT}->{warn})) {
+      WARN "Found deprecated option \"$key $value\"" . $config_file_statement . ": " . $warn_msg;
+    }
     if($opt->{deprecated}->{$value}->{ABORT} || $opt->{deprecated}->{DEFAULT}->{ABORT}) {
       ERROR 'Deprecated (incompatible) option found, refusing to continue';
       return undef;
     }
+    if($opt->{deprecated}->{$value}->{FAILSAFE_PRESERVE} || $opt->{deprecated}->{DEFAULT}->{FAILSAFE_PRESERVE}) {
+      unless($config_override{FAILSAFE_PRESERVE}) { # warn only once
+        WARN "Entering failsafe mode:";
+        WARN "  - preserving ALL snapshots for ALL subvolumes";
+        WARN "  - ignoring ALL targets (skipping backup creation)";
+        WARN "  - please read \"doc/upgrade_to_v0.23.0.md\" <http://digint.ch/btrbk/doc/upgrade_to_v0.23.0.html>";
+        $config_override{FAILSAFE_PRESERVE} = "Failsafe mode active (deprecated configuration)";
+      }
+      $config_override{snapshot_preserve_min} = 'all';
+      return $config;
+    }
     my $replace_key   = $opt->{deprecated}->{$value}->{replace_key};
     my $replace_value = $opt->{deprecated}->{$value}->{replace_value};
     if(defined($replace_key)) {
@@ -3747,6 +3759,11 @@ MAIN:
           }
           # TRACE(Data::Dumper->Dump([\@subvol_list], ["vinfo_raw_subvol_list{$droot}"]));
         }
+
+        if($config_override{FAILSAFE_PRESERVE}) {
+          ABORTED($droot, $config_override{FAILSAFE_PRESERVE});
+          WARN  "Skipping target \"$droot->{PRINT}\": $abrt";
+        }
       }
     }
   }