ORA-27086: unable to lock file - already in use

We have a database using NAS as its file storage , due to power outage , we had the server rebooted and database crashed.

When the server came back up and we tried to start the database , we got below error 
ORA-27086: unable to lock file - already in use

It seems the files are already locked at the isilon end and since the shut down was not very clean , those locks are still held on the isilon side.

Below are some commands which would help to resolve the issue.

To identify the server and the node on which the files are locked.....

isi_classic nfs clients list |grep  <database hostname>

( basically the database hostname should be the hostname that is registered with the NAS…..with regards to the NAS frame the database host would be a client to the NAS frame  )

isi_classic nfs clients list |grep  db_server

17052@db_server/10.38.15.207 exclusive [all] /ifs/netview/prd/NNM1/oradata/NNM1/small_data2.dbf
17052@db_server/10.38.15.207 exclusive [all] /ifs/netview/prd/NNM1/oradata/NNM1/small_index2.dbf
17052@db_server/10.38.15.207 exclusive [all] /ifs/netview/prd/NNM1/oradata/NNM1/small_data4.dbf

To remove the locks…..
 

isi_classic nfs clients remove <database hostname>/<NAS node holding the lock>

isi_classic nfs clients remove db_server/10.38.15.207


Database came up fine after this.