If we observe the below error in the database alert log file

ERROR: failed to establish dependency between database DEV and diskgroup resource ora.DATA.dg

Cause:

This error will be occur when there is ASM configured with you database.
It is due to the resource missing in the cluster registry services (CRS).But the error is harmless and will have no impact on database.

Solution:

The resource details can be found by executing the crs_stat -t command.

Go to $ORACLE_HOME/bin

Execute

srvctl add database -d DEV -o /u01/app/ora11g/product/11.2.0/dbhome_1

Once this is added Please re-run crs_stat -t from grid home and we can see a new resource added with name ora.dev.db

Then we can observe that the error in the database alert log will not occur and it will state successful establishment of connection between database and diskgroups.