A few minor changes:

It's now silent if everything is okay
Add a check for too many measurements in the database

pelab/opsdbcheck.pl

@@ -15,6 +15,7 @@ use libtbdb;
 use libwanetmondb;
 
 my $numMeas_ok = 100000;
+my $numMeas_too_many = 5000000;
 my $lastMeasTime_ok = time() - 60;  #last measurement must be within 60 seconds
 
 my $query 
@@ -25,9 +26,11 @@ if( scalar(@results) < $numMeas_ok ){
     print "fail: too few measurements in ops db\n";
     die -1;
 }
+if( scalar(@results) > $numMeas_too_many ){
+    print "fail: too many measurements in ops db\n";
+    die -1;
+}
 if( $results[0]->{unixstamp} < $lastMeasTime_ok ){
     print "fail: last measurement in ops db too old\n";
     die -2;
 }
-
-print "ok:\n";