[OpenAFS] Re: Mixing 1.4 and 1.6 fileservers

[Jeff White]

On 02/14/2013 05:26 AM, Hans-Werner Paulsen wrote:
> On Mon, Sep 24, 2012 at 12:14:52PM -0500, Andrew Deason wrote:
>> ... You can mix any fileserver versions in a cell, and any client
>> version can use any fileserver version, etc etc. If the servers are
>> running database server processes (vlserver, ptserver, etc) then mixing
>> versions is not supported, but should still work with those versions.
> What does happen, when I run 1.4.14 and 1.6.1 db servers simultaneously?
> Is it save to upgrade one db server while the db servers with the old
> versions are still running, when I do NOT modify the databases during the
> upgrade process?
>
> Best regards,
> HW
>
I would guess that the results would be unpredictable.  I doubt 
version-mixing is tested very much if at all.

We recently moved our DB servers from 1.2 to 1.6 without issue by 
bringing the old systems down entirely and moving the DB files to the 
new server with the lowest IP and letting ubik handle the rest (we 
reused the same IPs).  There was no issue and the new code can handle 
the old DB files just fine.  It did take a while for vlserver's DB to 
fully propagate to the slaves.  That may be because data was changing as 
it was trying to do it and ubik didn't like that.