diff --git a/tcp_tests/templates/underlay/mk22-lab-basic--user-data.yaml b/tcp_tests/templates/underlay/mk22-lab-basic--user-data.yaml
index b0dee66..b28d428 100644
--- a/tcp_tests/templates/underlay/mk22-lab-basic--user-data.yaml
+++ b/tcp_tests/templates/underlay/mk22-lab-basic--user-data.yaml
@@ -19,7 +19,7 @@
    # Block access to SSH while node is preparing
    - cloud-init-per once sudo iptables -A INPUT -p tcp --dport 22 -j DROP
    # Enable root access
-   - sed -i'.orig' -e's/without-password/yes/' /etc/ssh/sshd_config
+   - sed -i -e '/^PermitRootLogin/s/^.*$/PermitRootLogin yes/' /etc/ssh/sshd_config
    - service sshd restart
   output:
     all: '| tee -a /var/log/cloud-init-output.log /dev/tty0'