Redirect the log of the slave to /root/jenkins-slave.log
So a failure on that script can be investigated.
# We ignore errors on this script as we want to retry on errors.
cat > /root/jenkins-startup <<'EOF'
+&> /root/jenkins-startup.log
# Wait until the machine is set-up on creation
while ! (id ci >&/dev/null) || [ ! -f /home/ci/node_name ]; do
