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Re: 1.7 write-through proxy to 1.6 master

From: C. Michael Pilato <cmpilato_at_collab.net>
Date: Thu, 14 Jul 2011 12:30:13 -0400

On 07/14/2011 12:01 PM, Philip Martin wrote:
> It's possible to setup a 1.7 write-through proxy to a 1.6 master.

It's also a really bad idea.

The simple fact of the matter is that mixing and matching server versions in
a WebDAV proxy configuration doesn't work. And it really never has without
caveats, despite claims to the contrary. Feature negotiation happens at the
slave despite any undesirable consequences of the client acting on those
results when committing. HTTP v1 vs. v2 is one obvious place where stuff
fails. Another less-obvious one was with the introduction of merge
tracking, where the repository format version dictated support (or lack
thereof) for a client-visible feature. You might have had an existing 1.4
server (no merge tracking), popped up a 1.5 slave when that feature was
released, and now the clients are told that the server supports merge
tracking when it actually doesn't.

Complicating all of this is the fact that, as with the client's handling of
the working copy library, the server code has no concept of gracefully
degrading to support older flavors of itself as a general rule. Yeah, in
most cases stuff just kinda works okay. But we've merely been lucky, if
we're honest about it.

-- 
C. Michael Pilato <cmpilato_at_collab.net>
CollabNet   <>   www.collab.net   <>   Distributed Development On Demand

Received on 2011-07-14 18:30:50 CEST

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