setup_system.sh: bolster checks and quieten output

Bolster some checks so we don't try to edit files that do not
exist (for proxy setup for instance).
Also replace the 'sudo tee' commands with 'sudo bash -c "cat >"'
commands to reduce the echoing of the output to stdout.

Signed-off-by: Graham Whaley <graham.whaley@intel.com>

clr-k8s-examples/setup_system.sh

@@ -20,14 +20,14 @@ else
 fi
 
 sudo mkdir -p /etc/sysctl.d/
-cat <<EOT | sudo tee /etc/sysctl.d/60-k8s.conf
+cat <<EOT | sudo bash -c "cat > /etc/sysctl.d/60-k8s.conf"
 net.ipv4.ip_forward=1
 EOT
 sudo systemctl restart systemd-sysctl
 
 #Ensure the modules we need are preloaded
 sudo mkdir -p /etc/modules-load.d/
-cat <<EOT | sudo tee /etc/modules-load.d/k8s.conf
+cat <<EOT | sudo bash -c "cat > /etc/modules-load.d/k8s.conf"
 br_netfilter
 vhost_vsock
 overlay
@@ -35,7 +35,7 @@ EOT
 
 hostcount=$(grep '127.0.0.1 localhost' /etc/hosts | wc -l)
 if [ "$hostcount" == "0" ]; then
-	echo "127.0.0.1 localhost `hostname`" | sudo tee -a /etc/hosts
+	echo "127.0.0.1 localhost `hostname`" | sudo bash -c "cat >> /etc/hosts"
 else
 	echo "/etc/hosts already configured"
 fi
@@ -43,10 +43,11 @@ fi
 sudo systemctl daemon-reload
 # This will fail at this point, but puts it into a retry loop that
 # will therefore startup later once we have configured with kubeadm.
+echo "The following kubelet command may complain... it is not an error"
 sudo systemctl enable --now kubelet crio || true
 
 sudo mkdir -p /usr/libexec/cni /opt/cni
-sudo ln -s /usr/libexec/cni /opt/cni/bin
+[ ! -e /opt/cni/bin/cni ] && sudo ln -s /usr/libexec/cni /opt/cni/bin
 #Ensure that the system is ready without requiring a reboot
 sudo swapoff -a
 sudo modprobe br_netfilter vhost_vsock overlay
@@ -56,13 +57,17 @@ if [[ ${http_proxy} ]] || [[ ${HTTP_PROXY} ]]; then
   echo "Setting up proxy stuff...."
   # Setup IP for users too
   sed_val=${ADD_NO_PROXY//\//\\/}
-  sudo sed -i "/no_proxy/I s/$/,${sed_val}/g" /etc/environment
-  sudo sed -i "/no_proxy/I s/\"$/,${sed_val}\"/g" /etc/profile.d/proxy.sh
+  [ -f /etc/environment ] && sudo sed -i "/no_proxy/I s/$/,${sed_val}/g" /etc/environment
+  if [ -f /etc/profile.d/proxy.sh ]; then
+	  sudo sed -i "/no_proxy/I s/\"$/,${sed_val}\"/g" /etc/profile.d/proxy.sh
+  else
+	  echo "Warning, failed to find /etc/profile.d/proxy.sh to edit no_proxy line"
+  fi
 
   services=('crio' 'docker' 'kubelet')
   for s in "${services[@]}"; do
     sudo mkdir -p "/etc/systemd/system/${s}.service.d/"
-    cat << EOF | sudo tee "/etc/systemd/system/${s}.service.d/proxy.conf"
+    cat << EOF | sudo bash -c "cat > /etc/systemd/system/${s}.service.d/proxy.conf"
 [Service]
 Environment="HTTP_PROXY=${http_proxy}"
 Environment="HTTPS_PROXY=${https_proxy}"