[lug] Setting up failover in Linux?

[Rob Nagler]

Hi Will,

>   Clusters are run in maintenance mode during these situations so fail
> over will not occur until both systems are back to a similar state.

I can see how this would help prevent an accidental, automatic
failover wreaking havoc.  However, I'm interested in the problem that
the code and data are not part of the same transaction.

Perhaps I can explain it this way, assume the primary and secondary
are separated by a large enough distance that the disk blocks
associated with the data and code upgrade take "a while" to copy.
During that period, the primary fails.  What state is the secondary
in?  Can it take over?

Rob