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Re: [Xen-devel] Is it possible to access XenStore remotely?

Ian,

On Mon, 2009-08-24 at 17:05 +0100, Ian Jackson wrote:
> Tim Post writes ("Re: [Xen-devel] Is it possible to access XenStore 
> remotely?"):
> > I would warn you, XenStore is fragile and often fickle, I've crashed it
> > many times within a guest while working on split drivers for various
> > character devices.
> 
> If xenstored can be crashed then we should fix it.  Can you remember
> any of the things which caused it to fall over ?

Mostly, it was run away writers caught in a brain dead loop. It was not
difficult to DoS the store from within a guest accidentally or
deliberately.

I also remember using watches on a single key that changed frequently
without using xs_read_watch() since I already knew what fired, that
caused a total crash of xenstored.

I've also had xs_transaction_end() return -EAGAIN frequently on busy
systems.

The ocaml version of xenstored is much more resilient to abuse, be it
accidental or deliberate.

Cheers,
--Tim


-- 
Monkey + Typewriter = Echoreply ( http://echoreply.us )


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