OSFS (Object Store File System) enables VMFS volumes to be mounted as a single datastore for each host. Data on a VSAN datastore is stored in the form of data containers called objects, which is distributed across the cluster. An object can be a vmdk file, a snapshot, or the VM home folder. A reference object is also created and holds a VMFS volume and stores the virtual machine metadata files.

Logs for OSFS are captured in : /var/log/osfsd.log

How would you make a change in vSAN datastore with osfs-mkdir and osfs-rmdir?

It is not easy to create and remove any directory form VSAN  because the vSAN datastore is object based. In order to do that, special vSAN related commands exist to perform such tasks.

If you try and create a directory on VSAN you might get and error as :

# cd /vmfs/volumes/vsanDatastore

# mkdir TEST

mkdir: can’t create directory ‘TEST’: Function not implemented

How can we create/remove a directory ?

Step 1: Login to Esxi and access the folder …/bin/

# cd /usr/lib/vmware/osfs/bin

Step 2: List the contents 

# ls

objtool     osfs-ls     osfs-mkdir  osfs-rmdir  osfsd

Step 3: Verify that a directory called TEST does not exist

# ls -lh /vmfs/volumes/vsanDatastore/TEST

ls: /vmfs/volumes/vsanDatastore/TEST: No such file or directory

Step 4: Let’s create a Directory with the name TEST using osfs-mkdir

# ./osfs-mkdir /vmfs/volumes/vsanDatastore/TEST

54c0ba65-0c45-xxxx-b1f2-xxxxxxxxxxxx

Step 5: Verify that it exists

# ls -lh /vmfs/volumes/vsanDatastore/TEST

lrwxr-xr-x    1 root     root          12 Jan 09 21:03 /vmfs/volumes/vsanDatastore/TEST ->54c0ba65-0c45-xxxx-b1f2-xxxxxxxxxxxx

Step 6: Let’s try to Delete the directory now using osfs-rmdir

# ./osfs-rmdir /vmfs/volumes/vsanDatastore/TEST

Deleting directory 54c0ba65-0c45-xxxx-b1f2-xxxxxxxxxxxx in container id xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

backed by vsan (force=False)

Step 7: Verify that it has been removed

# ls -lh /vmfs/volumes/vsanDatastore/TEST

ls: /vmfs/volumes/vsanDatastore/TEST: No such file or directory