Re: [Libguestfs] Thoughts on nbdkit automatic reconnection
On Wed, Sep 18, 2019 at 01:59:01PM +0100, Richard W.M. Jones wrote:
We have a running problem with the nbdkit VDDK plugin where the VDDK
side apparently disconnects or the network connection is interrupted.
During a virt-v2v conversion this causes the entire operation to fail,
and since v2v conversions take many hours that's not a happy outcome.
(Aside: I should say that we see many cases where it's claimed that
the connection was dropped, but often when we examine them in detail
the cause is something else. But it seems like this disconnection
thing does happen sometimes.)
It turns out in the customer case that led us to talk about this, a
Checkpoint firewall was forcing the VDDK control connection to be
closed after an idle period. (The VDDK connection as a whole was not
actually idle because data was being copied over the separate data
port, but the firewall did not associate the two ports). I believe
nbdkit-retry-filter would have helped in this case because reopening
the VDDK connection will reestablish the control/metadata connection,
and therefore I am looking at an implementation now.
Rich.
--
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