diff --git a/bin/tests/system/resolver/tests.sh b/bin/tests/system/resolver/tests.sh
index d777ea1ab5..b9e5180f25 100755
--- a/bin/tests/system/resolver/tests.sh
+++ b/bin/tests/system/resolver/tests.sh
@@ -470,19 +470,19 @@ n=`expr $n + 1`
 echo_i "check prefetch of validated DS's RRSIG TTL is updated (${n})"
 ret=0
 $DIG $DIGOPTS +dnssec @10.53.0.5 ds.example.net ds > dig.out.1.${n} || ret=1
-ttl1=`awk '$4 == "DS" && $7 == "2" { print $2 - 2 }' dig.out.1.${n}`
+dsttl1=`awk '$4 == "DS" && $7 == "2" { print $2 - 2 }' dig.out.1.${n}`
 # sleep so we are in prefetch range
-sleep ${ttl1:-0}
+sleep ${dsttl1:-0}
 # trigger prefetch
 $DIG $DIGOPTS @10.53.0.5 ds.example.net ds > dig.out.2.${n} || ret=1
-ttl1=`awk '$4 == "DS" && $7 == "2" { print $2 }' dig.out.2.${n}`
+dsttl2=`awk '$4 == "DS" && $7 == "2" { print $2 }' dig.out.2.${n}`
 sleep 1
 # check that prefetch occured
 $DIG $DIGOPTS @10.53.0.5 ds.example.net ds +dnssec > dig.out.3.${n} || ret=1
 dsttl=`awk '$4 == "DS" && $7 == "2" { print $2 }' dig.out.3.${n}`
 sigttl=`awk '$4 == "RRSIG" && $5 == "DS" { print $2 }' dig.out.3.${n}`
-test ${dsttl:-0} -gt ${ttl2:-1} || ret=1
-test ${sigttl:-0} -gt ${ttl2:-1} || ret=1
+test ${dsttl:-0} -gt ${dsttl2:-1} || ret=1
+test ${sigttl:-0} -gt ${dsttl2:-1} || ret=1
 test ${dsttl:-0} -eq ${sigttl:-1} || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`