[Ocfs2-users] Shared Writeable MMAP

[Robert Schetterer]

Hi @ll i have a question about feature
Shared Writeable MMAP and its relation to concurent file use.

Background, over years i am hosting dovecot imap servers behind
loadbalancers on a drbd master/master setup shared formated storage
ocfs2 1.4.3 maildir without problems.

the dovecot wiki says

http://wiki2.dovecot.org/Director

Director can be used by Dovecot's IMAP/POP3/LMTP proxy to keep a
temporary user -> mail server mapping. As long as user has simultaneous
connections, the user is always redirected to the same server. Each
proxy server is running its own director process, and the directors are
communicating the state to each others. Directors are mainly useful for
setups where all of the mail storage is seen by all servers, such as
with NFS or a cluster filesystem

so the director service is most installed on the loadbalancers mainly
with nfs storage, proved to be a "must have"

after online investigation and long lasting reality tests , i guess "or
a cluster filesystem " isnt true for ocfs2, cause on drbd it works fine
with concurent files use ( i.e mailbox format maildir ) by feature
Shared Writeable MMAP.

Can sombody confirm this, or teach in easy words how it works ( or not )
and why ?


Best Regards
MfG Robert Schetterer

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