diff --git a/src/linux/lib/smartdc/mdata-get b/src/linux/lib/smartdc/mdata-get
index 9b0a3ed..e1f8fa9 100755
--- a/src/linux/lib/smartdc/mdata-get
+++ b/src/linux/lib/smartdc/mdata-get
@@ -43,9 +43,19 @@ case $(uname -s) in
 esac
 
 if [[ -n ${NC_SOCK} ]]; then
+  if [[ ! -e ${NC_SOCK} ]]; then
+    echo "mdata-get: socket not accessible" >&2
+    exit 2
+  fi
+
   coproc nc -U ${NC_SOCK}
   exec <&${COPROC[0]} 3>&${COPROC[1]}
 else
+  if [[ ! -e ${SERIAL_DEV} ]]; then
+    echo "mdata-get: socket not accessible" >&2
+    exit 2
+  fi
+
   exec <${SERIAL_DEV} 3>>${SERIAL_DEV}
 fi
 
diff --git a/src/linux/lib/smartdc/run-user-script b/src/linux/lib/smartdc/run-user-script
index d02704d..1c849b5 100755
--- a/src/linux/lib/smartdc/run-user-script
+++ b/src/linux/lib/smartdc/run-user-script
@@ -10,4 +10,6 @@ if [[ $? -eq 0 ]] ; then
     chmod +x /root/user-script
     exec /root/user-script
   fi
+else
+  rm -f /root/user-script
 fi
diff --git a/src/linux/lib/smartdc/set-root-authorized-keys b/src/linux/lib/smartdc/set-root-authorized-keys
index 2f5e469..a27a3e5 100755
--- a/src/linux/lib/smartdc/set-root-authorized-keys
+++ b/src/linux/lib/smartdc/set-root-authorized-keys
@@ -5,7 +5,7 @@
 
 if [[ ! -f /root/.ssh/authorized_keys ]]; then
   authorized_keys=$(/lib/smartdc/mdata-get root_authorized_keys 2>>/dev/console)
-  if [[ -n ${authorized_keys} ]]; then
+  if [[ $? -eq 0 && -n ${authorized_keys} ]]; then
     mkdir -p /root/.ssh
     echo "${authorized_keys}" > /root/.ssh/authorized_keys
     chmod 700 /root/.ssh