
How To Migrate Linux Servers Across Cloud Providers - 619Cloud
http://www.619cloud.com/blog/migrate-linux-servers-across-cloud-providers/
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prodigal_erik
Reading about efforts like this makes me glad we write a half-page spec file
and build an RPM for each service we've created. We're finally free of servers
whose configuration is a hand-crafted artwork needing this sort of attention.
We just "yum install" on a fresh machine (or a xen instance in dev or qa),
smoke test, and call it a day.

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moe
What a horrible idea.

~~~
garyrichardson
Why, in particular, do you think so?

On a one off basis, it sounds like a good idea.

I do think in the long run you're better off to use a build
process/documentation to allow rebuilding of hosts. This is especially true if
you're running 100's of instances.

~~~
moe
Exactly what you're saying.

If you need to maintain multiple hosts then use proper tooling, be it puppet,
chef, FAI, git, virtualization, or even a homegrown set of _bootstrap_
scripts.

Rsync'ing random stuff from one host to another will hardly end well, except
for truly one-off stuff that gets closely reviewed during the process.

File location and contents vary wildly, even between slightly different
[package] versions of the same distribution. Trying to automate that stuff
without even looking at what the package manager of the respective hosts has
to say is a recipe for disaster.

Sure, your script may work today right after you tested it with two near
identical RedHat hosts. I promise it will fail badly when you try to run it
again 6 months from now. Or rather, it will probably run nearly fine, but bury
some interesting surprises for you to find out about later...

