[stgt] [BUG] Tgt-1.0.8 exited unexpectedly

Hirokazu Takahashi taka at valinux.co.jp
Mon Sep 27 05:41:40 CEST 2010


Hi,

> > I want VastSky which is a cluster storage system to use TGT as its
> 
> Interesting. There are some similar experiments. IBM does the similar
> and I also did the similar with OpenStack. RedHat Hail does the
> similar with their own iSCSI target implementation.
> 
> Out of curiosity, can VastSky avoid reading the old data?
> 
> For example, WRITE goes to the three replica nodes, then WRITE to the
> same sector fails on the first replica node (e.g. timeout because the
> node is too busy) but succeeds with the rest two nodes (so the two
> nodes have the newer data).
> 
> Then if the two nodes having the new data are down, is it possible
> that an initiator gets the old data from the first node (when the
> initiator issues READ to the same sector)?

In that case, VastSky just returns an EIO error. I won't change this
policy since volumes VastSky serves are supposed to be used with
file-systems on them. If a volume returns the wrong date including
the old data will cause a filesystem corruption easily.

VastSky updates all the mirrors synchronously. And only after all
the I/O requests are completed, it tells the owner that the request
is done.

Thank you,
Hirokazu Takahashi.
--
To unsubscribe from this list: send the line "unsubscribe stgt" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html



More information about the stgt mailing list