Update domainjoin.sh

domainjoin.sh

@@ -10,12 +10,13 @@ if [ -f /etc/debian_version ]; then
     wget -O /etc/apt/sources.list.d/pbiso.list http://repo.pbis.beyondtrust.com/apt/pbiso.list 
     apt update
     apt install -y pbis-open
-fi
-
-if [ -f /etc/redhat-release ]; then
+else if [ -f /etc/redhat-release ]; then
     wget -O /etc/yum.repos.d/pbiso.repo http://repo.pbis.beyondtrust.com/yum/pbiso.repo
     yum clean all
     yum install pbis-open
+else
+    echo "Unable to determine linux distro"
+    exit
 fi
 
 # ask for the domain, username, and password