diff --git a/bench.sh b/bench.sh
index 1f04135d..d89a96e4 100755
--- a/bench.sh
+++ b/bench.sh
@@ -2,21 +2,27 @@
 SKIP_CONFIG=false
 PROFILE="${PROFILE:-}"
 GROUP="${GROUP:-scenarios}"
+CAPTURE=false
+SINGLE_CAPTURE=false
 
 usage() {
   echo "Usage: bench.sh [-p PROFILE] [-C] [num_runs]"
   echo "Options:"
   echo -e "\\t-p CE|PRO default is autodetect"
   echo -e "\\t-C skips configuration of the environment"
+  echo -e "\\t-k capture messages with tcpdump, per scenario"
+  echo -e "\\t-K capture messages with tcpdump. One big file for all scenarios"
   echo -e "\\t-x set GROUP scenario. Default: scenarios"
   echo -e "\\t-h this help"
   echo -e "num_runs default is 20"
 }
 
-while getopts 'hCp:x:' opt; do
+while getopts 'hCkKp:x:' opt; do
   case $opt in
     h) usage; exit 0;;
     C) SKIP_CONFIG=true;;
+    k) SINGLE_CAPTURE=true;;
+    K) CAPTURE=true;;
     p) PROFILE=${OPTARG};;
     x) GROUP=${OPTARG};;
 	*) echo "Unknown option $opt"; usage; exit 1;;
@@ -44,6 +50,12 @@ fi
 NUM=${1:-20}
 RUN_OPS=(-C -c -r -p"${PROFILE}" -x"${GROUP}")
 
+if "${CAPTURE}" ; then
+  RUN_OPS+=(-K)
+elif "${SINGLE_CAPTURE}" ; then
+  RUN_OPS+=(-k)
+fi
+
 # clean previous
 rm -rf log_* result_*
 
diff --git a/run_tests.sh b/run_tests.sh
index d513431a..3a4edc30 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -22,6 +22,7 @@ TIMEOUT=${TIMEOUT:-300}
 SHOW_SCENARIOS=false
 SKIP_CONFIG=false
 CAPTURE=false
+SINGLE_CAPTURE=false
 FIX_RETRANS=false
 MEMDBG=false
 CDR=false
@@ -226,7 +227,8 @@ usage() {
   echo -e "\\t-p CE|PRO default is autodetect"
   echo -e "\\t-l print available SCENARIOS in GROUP"
   echo -e "\\t-C skips configuration of the environment"
-  echo -e "\\t-K capture messages with tcpdump"
+  echo -e "\\t-k capture messages with tcpdump, per scenario"
+  echo -e "\\t-K capture messages with tcpdump. One big file for all scenarios"
   echo -e "\\t-x set GROUP scenario. Default: scenarios"
   echo -e "\\t-t set timeout in secs for pid_watcher.py [PRO]. Default: 300"
   echo -e "\\t-r fix retransmission issues"
@@ -238,12 +240,13 @@ usage() {
   echo "BIN_DIR:${BIN_DIR}"
 }
 
-while getopts 'hlCcp:Kx:t:rm' opt; do
+while getopts 'hlCcp:kKx:t:rm' opt; do
   case $opt in
     h) usage; exit 0;;
     l) SHOW_SCENARIOS=true;;
     C) SKIP_CONFIG=true;;
     p) PROFILE=${OPTARG};;
+    k) SINGLE_CAPTURE=true;;
     K) CAPTURE=true;;
     x) GROUP=${OPTARG};;
     t) TIMEOUT=${OPTARG};;
@@ -362,6 +365,8 @@ fi
 
 if "${CAPTURE}" ; then
   capture
+elif "${SINGLE_CAPTURE}" ; then
+  OPTS+=(-K)
 fi
 
 for t in "${SCEN[@]}"; do