How can I delete repo manually on a ODA?

I'm using ODA X5-2 virtaul platform(ODA version : 12.1.2.10.0).

I'd like to delete repo "srepo"(name of the repository) by using "oakcli delete repo".

# oakcli show repo    

NAME                     TYPE       NODENUM FREE SPACE STATE     SIZE

===========================================================

odarepo1                 local     0              N/A N/A       N/A

odarepo2                 local     1              N/A N/A       N/A

srepo                     shared     0           99.98% ONLINE     512000.0M

srepo                     shared     1           99.98% ONLINE     512000.0M

First, I tried to stop repo, but I didn't.

# oakcli stop repo srepo

OAKERR:8032 NFS Unmount Failure on DOM0 for repo srepo

OAKERR:8032 NFS Unmount Failure on DOM0 for repo srepo

So, in this reason, I tried to stop repo on the each node. But, the result was same.