I ran into this change in behavior from the vSphere 4.x CLI. You can use vifs to upload a file to an ESX's datastore while the ESX is in maintenance mode, but if you try to remove it the operation fails until you exit maintenance mode:
vi-admin@localhost:/tmp> # Started in maintenance mode on the ESXi host
vi-admin@localhost:/tmp> vifs --server 10.127.130.230 --put /tmp/foo.txt "[datastore1] /foo.txt"
Enter username: root
Enter password:
Uploaded file /tmp/foo.txt to /foo.txt successfully.
vi-admin@localhost:/tmp> vifs --server 10.127.130.230 --rm "[datastore1] /foo.txt"
Enter username: root
Enter password:
Remove '/foo.txt'? (y/n) : y
Unable to delete [datastore1] /foo.txt:
The operation is not allowed in the current state.
vi-admin@localhost:/tmp> # Took the ESXi host out of maintenance mode
vi-admin@localhost:/tmp> vifs --server 10.127.130.230 --rm "[datastore1] /foo.txt"
Enter username: root
Enter password:
Remove '/foo.txt'? (y/n) : y
Deleted file '[datastore1] /foo.txt' successfully.
vi-admin@localhost:/tmp>
I didn't find this change in behavior called out in the documentation, so it may be an unintended regression. Has anyone else run into this problem and found a workaround other than taking the ESXi host out of maintenance mode?