[tahoe-dev] How do lease renewal and repair work?

Shawn Willden shawn at willden.org
Tue Jan 11 15:19:04 UTC 2011

Specifically, what I'm wondering what happens if a client running a
deep-check --repair --add-lease tries to add a lease on an existing share
and the storage server refuses the lease renewal?  Will the repairer assume
that the unrenewed share needs to be placed somewhere else?  Or will the
client have to wait until the unrenewed share actually expires before the
repairer will place another copy?

The motivation is that I'm thinking about how storage nodes can withdraw
gracefully from the grid.  If the storage servers can refuse to renew leases
and if the repairer assumes that unrenewed shares need to be placed
elsewhere, then it should be very simple to create a new storage server
configuration flag "withdrawing", which tells the storage server to refuse
new shares, and also to refuse lease renewals.  Then, with lease expiration
turned on, all of the shares it's holding will eventually expire, but all of
the clients who own those shares will have ample opportunity to relocate
them.  When the last of the withdrawing server's shares expire, then it can
be shut down.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://tahoe-lafs.org/pipermail/tahoe-dev/attachments/20110111/ced98911/attachment.html>

More information about the tahoe-dev mailing list