diff --git a/tools/pretty_tox.sh b/tools/pretty_tox.sh
index 55dd140429..e1bc9acfcb 100755
--- a/tools/pretty_tox.sh
+++ b/tools/pretty_tox.sh
@@ -1,6 +1,6 @@
-#!/usr/bin/env bash
-
-set -o pipefail
+#! /bin/sh
 
 TESTRARGS=$1
-python -m neutron.openstack.common.lockutils python setup.py testr --slowest --testr-args="--subunit $TESTRARGS" | $(dirname $0)/subunit-trace.py -f
+
+exec 3>&1
+status=$(exec 4>&1 >&3; ( python -m neutron.openstack.common.lockutils python setup.py testr --slowest --testr-args="--subunit $TESTRARGS"; echo $? >&4 ) | $(dirname $0)/subunit-trace.py -f) && exit $status
diff --git a/tox.ini b/tox.ini
index 78abf20d61..2e7d2e48d5 100644
--- a/tox.ini
+++ b/tox.ini
@@ -12,9 +12,9 @@ usedevelop = True
 install_command = pip install -U {opts} {packages}
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
-whitelist_externals = bash
+whitelist_externals = sh
 commands =
-  bash tools/pretty_tox.sh '{posargs}'
+  sh tools/pretty_tox.sh '{posargs}'
 # there is also secret magic in pretty_tox.sh which lets you run in a fail only
 # mode. To do this define the TRACE_FAILONLY environmental variable.