[ILUG] Sync-ing kmail on desktop and laptop

[Gavin McCullagh]

Hi,

On Wed, 18 Apr 2007, Timothy Murphy wrote:

> > Email clients fetch only the messages I select on demand and store &
> > cache them whatever way they want. I have Outlook (sorry), Evolution,
> > Mutt, my phone and Roundcube (IMAP webmail) all working from the same
> > central mailstore and accessible anywhere with an internet connection.
> > If I delete, flag, move or mark read a message on one client, the
> > changes are instantly reflected elsewhere.
> 
> I realise I could do something like this, but it seems much more
> complicated than just exporting ~/Mail with NFS.

It really isn't more complicated.  It seems you're just more familiar with
NFS than IMAP.

> What is the advantage of doing it your way?

Not all of these will directly affect you but some of them must.  Purely
off the top of my head:

1. When you open a folder, NFS will have to send the entire folder (could
   be >100MB) over the wire/airwaves so the client can sort it and display
   it.  By contrast, IMAP will usually just send the headers and only get
   the email body when you want to read it.  If your mail client keeps
   indexes, it will write probably read/write them back to the server with
   nfs and read/write them locally with IMAP.

2. If you search for a mail, your email client can ask the IMAP server to
   do the search and pass back the headers of the results only.  NFS would
   have to send over the entire mail folder (be it mbox, maildir, whatever)
   to let the client search it.

3. Your mail client can be told to cache imap folders.  It's unlikely to
   cache NFS shares (though I guess you could use rsync, but that would be
   dangerous as it has to be writable at both ends).  If your desktop is
   down your email can still be available to the laptop and your laptop
   doesn't have to request an email every time you look at it.

4. NFS is not easily done on all platforms (does anyone in your house use
   windows?)

5. IMAP works easily over SSL for better security.

6. IMAP can easily be ssh tunnelled for even more secure remote access when
   your laptop is not on your home network.

7. IMAP is properly authenticated, NFS isn't usually so any punter can
   connect to an nfs share and read/write anything.

The only major fly in the ointment with IMAP is that there doesn't seem to
be a general way to distribute addressbooks over imap.  So, you need to
maintain an addressbook on each client (or use nfs, rsync, ldap, etc.) to
keep it in sync.  Unless kmail has some addressbook over imap hack?

If you want it _exactly_ the same, maybe you should just do:

tim at laptop ~> ssh -X desktop kmail

the config is minimal too.

Gavin