diff --git a/lib/int.pm b/lib/int.pm
index 8dba8d1..8d37f98 100644
--- a/lib/int.pm
+++ b/lib/int.pm
@@ -32,8 +32,39 @@ sub int_init {
 	my ($package, $config, $debug) = @_;
 	my $rrd = $config->{base_lib} . $package . ".rrd";
 
+	my $info;
+	my @rra;
+	my @tmp;
+	my $n;
+
+	my @average;
+	my @min;
+	my @max;
+	my @last;
+
+	if(-e $rrd) {
+		$info = RRDs::info($rrd);
+		for my $key (keys %$info) {
+			if(index($key, 'rra[') == 0) {
+				if(index($key, '.rows') != -1) {
+					push(@rra, substr($key, 4, index($key, ']') - 4));
+				}
+			}
+		}
+		if(scalar(@rra) != 12 + (4 * $config->{max_historic_years})) {
+			logger("$myself: Detected size mismatch between 'max_historic_years' (" . $config->{max_historic_years} . ") and $rrd (" . ((scalar(@rra) -12) / 4) . "). Resizing it accordingly. All historic data will be lost. Backup file created.");
+			rename($rrd, "$rrd.bak");
+		}
+	}
+
 	if(!(-e $rrd)) {
 		logger("Creating '$rrd' file.");
+		for($n = 1; $n <= $config->{max_historic_years}; $n++) {
+			push(@average, "RRA:AVERAGE:0.5:1440:" . (365 * $n));
+			push(@min, "RRA:MIN:0.5:1440:" . (365 * $n));
+			push(@max, "RRA:MAX:0.5:1440:" . (365 * $n));
+			push(@last, "RRA:LAST:0.5:1440:" . (365 * $n));
+		}
 		eval {
 			RRDs::create($rrd,
 				"--step=60",
@@ -296,19 +327,19 @@ sub int_init {
 				"RRA:AVERAGE:0.5:1:1440",
 				"RRA:AVERAGE:0.5:30:336",
 				"RRA:AVERAGE:0.5:60:744",
-				"RRA:AVERAGE:0.5:1440:365",
+				@average,
 				"RRA:MIN:0.5:1:1440",
 				"RRA:MIN:0.5:30:336",
 				"RRA:MIN:0.5:60:744",
-				"RRA:MIN:0.5:1440:365",
+				@min,
 				"RRA:MAX:0.5:1:1440",
 				"RRA:MAX:0.5:30:336",
 				"RRA:MAX:0.5:60:744",
-				"RRA:MAX:0.5:1440:365",
+				@max,
 				"RRA:LAST:0.5:1:1440",
 				"RRA:LAST:0.5:30:336",
 				"RRA:LAST:0.5:60:744",
-				"RRA:LAST:0.5:1440:365",
+				@last,
 			);
 		};
 		my $err = RRDs::error;