diff --git a/stack.sh b/stack.sh
index ef4591e232..93e4541990 100755
--- a/stack.sh
+++ b/stack.sh
@@ -212,7 +212,7 @@ fi
 # Some distros need to add repos beyond the defaults provided by the vendor
 # to pick up required packages.
 
-if [[ is_fedora && $DISTRO == "rhel6" ]]; then
+if is_fedora && [ $DISTRO == "rhel6" ]; then
     # Installing Open vSwitch on RHEL requires enabling the RDO repo.
     RHEL6_RDO_REPO_RPM=${RHEL6_RDO_REPO_RPM:-"http://rdo.fedorapeople.org/openstack-icehouse/rdo-release-icehouse.rpm"}
     RHEL6_RDO_REPO_ID=${RHEL6_RDO_REPO_ID:-"openstack-icehouse"}
@@ -223,7 +223,7 @@ if [[ is_fedora && $DISTRO == "rhel6" ]]; then
     fi
 fi
 
-if [[ is_fedora && ( $DISTRO == "rhel6" || $DISTRO == "rhel7" ) ]]; then
+if is_fedora && [[ $DISTRO == "rhel6" || $DISTRO == "rhel7" ]]; then
     # RHEL requires EPEL for many Open Stack dependencies
 
     # note we always remove and install latest -- some environments
@@ -347,7 +347,7 @@ function echo_nolog {
     echo $@ >&3
 }
 
-if [[ is_fedora && $DISTRO == "rhel6" ]]; then
+if is_fedora && [ $DISTRO == "rhel6" ]; then
     # poor old python2.6 doesn't have argparse by default, which
     # outfilter.py uses
     is_package_installed python-argparse || install_package python-argparse