samba - Sep 2015 - Cache auth credentials on Samba domain member

Hi all,
I have the following setup:

DOMAIN CONTROLLER (Win2003) <-> VPN TUNNEL <-> REMOTE SAMBA SERVER
<->
REMOTE CLIENTS

The remote samba server is a CentOS 6.6 x86_64 server, with Samba 
version 3.6.23. It acts as a domain member, configured with security = 
ads; it uses winbind to enumerate Windows users and to grant share access.

Such setup works quite well, but I wonder how to cope with VPN 
connection losses. At the moment, if the VPN connection goes down the 
Samba server is (obviously) unable to authenticate users against the 
domain controller, and the remote office's users can not work.

My question is: it is possible to cache the credentials or the 
authentication status such as a connectivity loss does not impair the 
remote client? I tried configuring "winbind cache time" and
"winbind
offline logon", but without success.

Thanks you all.

-- 
Danti Gionatan
Supporto Tecnico
Assyoma S.r.l. - www.assyoma.it
email: g.danti at assyoma.it - info at assyoma.it
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