[chef] Re: Re: Re: how to make one node tell another to do some work

[Denis Haskin < >]

So the db servers are managed with chef?

I guess if you really felt like you needed to use chef to do this, I guess my thinking might be that you have a role that corresponds to each customer's database, e.g. "customerA_db_server", "customerB_db_server", etc.

Then I guess (handwaving like crazy here) you could change the roles for the 2 nodes and when the nodes converge, somehow the node that *used* to have customer A's db would have to know to dump it somewhere, and then the node that is now responsible for it would know it has to look for the dump somewhere, and load it.

This feels really ugly, though, and square-peg-in-round-hole-ish.  And maybe it's just a variant on what you were proposing at first with attributes and such.  I dunno.

--

Denis Haskin

On Fri, Sep 28, 2012 at 1:33 PM, Jesse Campbell < " target="_blank"> > wrote:

I'm moving this from an orchestration system into chef because it does
not seem to me to be a terribly complex problem, and adding a new
orchestration system to the puzzle seems like a lot of work for such a
small task.

Maybe I was too vague in what I'm trying to do?

Each customer DB server knows what databases are running on it.

Sometimes one of the customer DB servers gets overloaded and we have
to migrate a database from one server to another.

Is there another simple solution to telling server A to dump the DB to
disk, and tell server B to pick it up?

I don't think that a work queue will work here, because only one DB is
relevant for the task... setting up 40 work queues for the 40 db
servers seems quite messy, and then I need to maintain yet another
service?

-Jesse