ABCs of z/OS System Programming Volume 3 - IBM Redbooks

For LOG(ALL) you need to define a logstream in which changes to the data sets are
logged.
Non-recoverable data sets
A data set whose LOG parameter is undefined or NONE is considered as non-recoverable.
Non-CICS access to recoverable and non-recoverable data sets
VSAM RLS supports non-recoverable files. Non-recoverable means CICS does not do
transactional recovery (logging, commit, backout). VSAM RLS provides record locking and file
integrity across concurrently executing CICS and batch applications. Transactional recovery
is not provided. This is because VSAM RLS does not provide undo logging and two-phase
commit/backout support. Most transactions and batch jobs are not designed to use this form
of data sharing.
Non-CICS read/write access for recoverable data sets that are open by CICS is not allowed.
The recoverable attribute means that when the file is accessed in RLS mode, transactional
recovery is provided. With RLS, the recovery is only provided when the access is through
CICS file control, so RLS does not permit a batch (non-CICS) job to open a recoverable file
for OUTPUT.
Transactional recovery is described in 7.11, “Transactional recovery” on page 394.
Chapter 7. DFSMS Transactional VSAM Services 393