remove the systemd unit and call the script through systemd-run

mantle/kola/tests/ostree/sync.go

@@ -173,19 +173,7 @@ storage:
                  sleep 0.5; \
                 done; \
              done) &
-           done
-systemd:
-  units:
-  - name: write-to-nfs.service
-    enabled: false
-    contents: |
-      [Unit]
-      ConditionFirstBoot=true
-      [Service]
-      Type=oneshot
-      RemainAfterExit=yes
-      ExecStart=/usr/local/bin/nfs-random-write.sh
-      Restart=on-failure`)
+           done`)
 	opts := platform.MachineOptions{
 		MinMemory: 2048,
 	}
@@ -225,9 +213,10 @@ systemd:
 func doSyncTest(c cluster.TestCluster, client platform.Machine) {
 	c.RunCmdSync(client, "sudo touch /var/tmp/data3/test")
 	// Continue write
-	_, err := c.SSH(client, `sudo systemctl enable --now write-to-nfs.service`)
+	//_, err := c.SSH(client, `sudo systemctl enable --now write-to-nfs.service`)
+	_, err := c.SSH(client, "sudo systemd-run sh -c '/usr/local/bin/nfs-random-write.sh'")
 	if err != nil {
-		c.Fatalf("failed to start service: %v", err)
+		c.Fatalf("failed to start write-to-nfs: %v", err)
 	}
 
 	// Create a stage deploy using kargs while writing
@@ -241,10 +230,7 @@ func doSyncTest(c cluster.TestCluster, client platform.Machine) {
 	c.Log("Set link down and rebooting.")
 	// Skip the error check as it is expected
 	cmd := fmt.Sprintf("sudo systemd-run sh -c 'ip link set %s down && sleep 5 && systemctl reboot'", netdevice)
-	_, err = c.SSH(client, cmd)
-	if err != nil {
-		c.Fatalf("failed to set down link and reboot: %v", err)
-	}
+	_, _ = c.SSH(client, cmd)
 
 	err = util.Retry(8, 10*time.Second, func() error {
 		// Look for the kernel argument test=1