Chapter 9. Installing and Managing DRBD Services / 9.4. Testing the DRBD Service
	9.3. Configuring the DRBD Service		9.5. Troubleshooting DRBD

Testing the DRBD Service

If the install and configuration procedures worked as expected, you are ready to run a basic test of the drbd functionality. This test also helps with understanding how the software works.

Test the DRBD service on node 1.
1. Open a terminal console, then log in as the root user or equivalent.
2. Create a mount point on node 1, such as /r0mount, by entering
```
mkdir /r0mount
```
3. Mount the drbd device by entering
```
mount -o rw /dev/drbd0 /r0mount
```
4. Create a file from the primary node by entering
```
touch /r0mount/from_node1
```
Test the DRBD service on node 2.
1. Open a terminal console, then log in as the root user or equivalent.
2. Dismount the disk on node 1 by typing the following command on node 1:
```
umount /r0mount
```
3. Downgrade the DRBD service on node 1 by typing the following command on node 1:
```
drbdadm secondary r0
```
4. On node 2, promote the DRBD service to primary by entering
```
drbdadm primary r0
```
5. On node 2, check to see if node 2 is primary by entering
```
rcdrbd status
```
6. On node 2, create a mount point such as /r0mount, by entering
```
mkdir /r0mount
```
7. On node 2, mount the DRBD device by entering
```
mount -o rw /dev/drbd0 /r0mount
```
8. Verify that the file you created on node 1 in Step 1.d is viewable by entering
```
ls /r0mount
```
  The /r0mount/from_node1 file should be listed.
If the service is working on both nodes, the DRBD setup is complete.
Set up node 1 as the primary again.
1. Dismount the disk on node 2 by typing the following command on node 2:
```
umount /r0mount
```
2. Downgrade the DRBD service on node 2 by typing the following command on node 2:
```
drbdadm secondary r0
```
3. On node 1, promote the DRBD service to primary by entering
```
drbdadm primary r0
```
4. On node 1, check to see if node 1 is primary by entering
```
service drbd status
```
To get the service to automatically start and fail over if the server has a problem, you can set up DRBD as a high availability service with HeartBeat 2.
For information about installing and configuring HeartBeat 2 for SUSE® Linux Enterprise Server 10, see the HeartBeat 2 Installation and Setup Guide on the Novell Documentation Web site for SUSE Linux Enterprise Server 10.