Testing Data Replication/Synchronize on DRBD

After configuration DRBD in the previous article, we must test first for ensure whether DRBD has been working properly or not. This is some testing to ensure DRBD has been worked
# TESTING ON NODE1
– Create folder tmp in /mnt folder

1.mkdir /mnt/tmp
– Mount DRBD devices into tmp folder who has been created

1.mount /dev/drbd0 /mnt/tmp
– Create file/folder into tmp folder

1.touch /mnt/tmp/created-on-node1.txt
– Please check whether file created-on-node1.txt has been there

1.ls /mnt/tmp/
– For testing/check on node2, umount DRBD devices and demoting into secondary

1.umount /dev/drbd0
2.drbdadm secondary r0
– Make sure DRBD has been demoted into Secondary

1.service drbd status
# TESTING ON NODE2
– Create folder tmp in /mnt folder

1.mkdir /mnt/tmp
– Promoting DRBD into Primary

1.drbdadm primary r0
– Mount DRBD devices into tmp folder who has been created

1.mount /dev/drbd0 /mnt/tmp
– Please check whether file created-on-node1.txt has been there too

1.ls /mnt/tmp/
If the file has been there, it’s meant DRBD has been replicated
– Umount DRBD devices, demoting again into secondary and promoting node1 into primary

1.umount /dev/drbd0
2.drbdadm secondary r0
3.service drbd status
# PROMOTING NODE1 INTO PRIMARY
run the following command on node1

1.service drbd status
2.drbdadm primary r0
Good luck and hopefully useful

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