diff --git a/lower-constraints.txt b/lower-constraints.txt
index fd5e25c9..a68ae4fe 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -46,7 +46,7 @@ smmap==0.9.0
 snowballstemmer==1.2.1
 Sphinx==1.6.2
 sphinxcontrib-websupport==1.0.1
-stestr==2.0.0
+stestr==2.1.0
 stevedore==1.20.0
 testscenarios==0.4
 testtools==2.2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 3db674e3..ffbe9cc8 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -5,7 +5,7 @@ hacking>=1.1.0,<1.2.0 # Apache-2.0
 
 fixtures>=3.0.0 # Apache-2.0/BSD
 testscenarios>=0.4 # Apache-2.0/BSD
-stestr>=2.0.0 # Apache-2.0
+stestr>=2.1.0 # Apache-2.0
 testtools>=2.2.0 # MIT
 oslotest>=3.2.0 # Apache-2.0
 
diff --git a/tox.ini b/tox.ini
index a3dffb79..1d32d6bd 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,16 +7,17 @@ envlist = py35,py27,pep8
 install_command = pip install {opts} {packages}
 whitelist_externals =
   find
-setenv = OS_STDOUT_CAPTURE=1
-         OS_STDERR_CAPTURE=1
-         OS_TEST_TIMEOUT=60
+setenv =
+  OS_STDOUT_CAPTURE={env:OS_STDOUT_CAPTURE:1}
+  OS_STDERR_CAPTURE={env:OS_STDERR_CAPTURE:1}
+  OS_TEST_TIMEOUT={env:OS_TEST_TIMEOUT:60}
 deps =
   -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
 commands =
   find . -type f -name "*.pyc" -delete
-  stestr run {posargs}
+  stestr run --suppress-attachments {posargs}
   stestr slowest
 
 [testenv:lower-constraints]
@@ -55,8 +56,8 @@ basepython = python3
 whitelist_externals = rm
 deps = -r{toxinidir}/doc/requirements.txt
 commands =
-    rm -fr doc/build
-    sphinx-build -W -b html doc/source doc/build/html {posargs}
+  rm -fr doc/build
+  sphinx-build -W -b html doc/source doc/build/html {posargs}
 
 [testenv:bandit]
 basepython = python3