diff --git a/build.sh b/build.sh
index b30c91bcc9b6f1af60fb38aac7c38e8aaaf5b2e9..02ecaeb5c502a8b5daed4e7ef9c3fc1e64f6b5a4 100755
--- a/build.sh
+++ b/build.sh
@@ -12,8 +12,7 @@ BUILD_PACKAGES="
 
 # Packages required to serve the website and run the services.
 PACKAGES="
-	bind9
-	bind9utils
+	bind9-utils
 	curl
 	git
 	openssh-client
@@ -41,9 +40,9 @@ if [ "x$(which install_packages)" = "x" ]; then
     }
 fi
 
+umask 022
 set -x
 set -e
-umask 022
 
 apt-get -q update
 install_packages ${BUILD_PACKAGES} ${PACKAGES}
@@ -98,6 +97,8 @@ chmod 700 /root/.vagrant.d
 chmod 600 /root/.vagrant.d/insecure_private_key
 
 # Remove packages used for installation.
+set +x
+set +e
 apt-get remove -y --purge ${BUILD_PACKAGES}
 apt-get autoremove -y
 apt-get clean