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Re: [Xen-devel] organizing virtual machines

Tom Hibbert wrote:
There is no requirement for seperating partitions on installation. This
is considered a best practice because in the event of a partition
faliure it increases the chance of recovering at least part of the
system. In the purists world, / is mounted read-only and the only parts
of the disk that can be written to without mounting readwrite are /var
and /home.

(knock wood) I've never had a partition failure. They have always been more on the lines of "*%#@%@ I lost another drive".

Absolutely true. However, it is possible to have a shared root/usr using
NFS, with independent /var, /home and /etc. This is a common
configuration for clusters and big iron.

intriguing. Makes sense and one could also do this with the dom0 serving all the other virtual machines. would have some problems with /etc however

Dogs breakfast?

yea.  a.k.a. "recycling" and in the wintertime "Poopsicles".

Only in the event of badly constructed packages or an
inexperienced aministrator installing from source should there ever be
any configuration data stored outside of /etc. This is the sole reason
/etc exists. I don't consider it a dogs breakfast at all, even under

I must politely disagree. In the example you gave above where root end-user are shared, what happens when you change a program that also has a related change in /etc? At best, nothing bad happens. At worst, you start getting random failures that drive you mad until you finally get all of the images changed. Sometimes it's a simple replication. More often than not it's customized changes on all machines.

Even updating a single machine it can be a "this sucks" moment. I cannot tell you the number of times I have updated gentoo and found that I had to slog through 50 configuration file changes.

so, the reason I consider virtually all system configuration directories, registries etc. a dogs breakfast is that they don't handle change well and the changes are not replicated properly.

my fantasy world for proper system configuration management would record baseline and changes so that when baseline changes one can re-create the working configuration set (i.e. /etc). For a virtual machine environment like xen, one could have virtual machine associated changes with a common baseline so that when you update your executables and configuration directory, all the changes replicate properly or can be flagged for human attention.

I'm planning a working on this when I have some spare neurons.



The basis of Abelard's philosophy, which he taught to Heloise, was
that logic had to be applied to religion in order to arrive at the

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