Highly Available Zope
From my understanding of ZEO, a single ZODB is shared between multiple Zope application clients, giving a performance boost by offloading onto the multiple app clients. This leaves the ZODB machine as a single point of failure. We've had success in the past using DRBD to make relational databases highly available across multiple machines, I'm curious if anyone has done something similar to make the ZODB highly available in this manner, or if I'm misunderstanding a part of ZEO which handles this single point of failure. Thanks! -- - David A. Riggs <lukewarm@ultrasoul.com>
Hi David, ZC sells a commercial product named "ZRS" which eliminates a ZEO storage as a single point of failure. See zope.com for more information. - C On Wed, 2003-07-16 at 15:20, David A. Riggs wrote:
From my understanding of ZEO, a single ZODB is shared between multiple Zope application clients, giving a performance boost by offloading onto the multiple app clients.
This leaves the ZODB machine as a single point of failure. We've had success in the past using DRBD to make relational databases highly available across multiple machines, I'm curious if anyone has done something similar to make the ZODB highly available in this manner, or if I'm misunderstanding a part of ZEO which handles this single point of failure.
Thanks!
-- - David A. Riggs <lukewarm@ultrasoul.com>
On Wednesday 16 July 2003 20:39, Chris McDonough wrote:
Hi David,
ZC sells a commercial product named "ZRS" which eliminates a ZEO storage as a single point of failure. See zope.com for more information.
For a free alternative to ZRS, DirectoryStorage supports replication inside the storage. Its replication capability was originally developed as an online backup / warm standby solution, but when combined with something like heartbeat from the linux-ha project it can also provide high availability. http://dirstorage.sourceforge.net/ I undestand that ZRS can also provide a scalability advantage if you have read-only ZEO clients; ZRS secondaries can act as read-only ZEO servers. You may find that DirectoryStorage has other advantages in the broader 'disaster preparedness' context. For example it is the only storage that applies transaction semantics to incremental backups, it has a very thorough checking tool, and it has a range of other features providing fault-tolerance. -- Toby Dickenson http://www.geminidataloggers.com/people/tdickenson
Chris McDonough wrote:
Hi David,
ZC sells a commercial product named "ZRS" which eliminates a ZEO storage as a single point of failure. See zope.com for more information.
I thought it just provided a 'hot backup' rather than true replication. Can you clarify? cheers, Chris
Consider running the ZEO server on a solution e.g. on a cluster with failover mechanism. You might also checkout ZRS from Zope Corp. -aj --On Mittwoch, 16. Juli 2003 15:20 Uhr -0400 "David A. Riggs" <lukewarm@ultrasoul.com> wrote:
From my understanding of ZEO, a single ZODB is shared between multiple Zope application clients, giving a performance boost by offloading onto the multiple app clients.
This leaves the ZODB machine as a single point of failure. We've had success in the past using DRBD to make relational databases highly available across multiple machines, I'm curious if anyone has done something similar to make the ZODB highly available in this manner, or if I'm misunderstanding a part of ZEO which handles this single point of failure.
Thanks!
-- - David A. Riggs <lukewarm@ultrasoul.com>
participants (5)
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Andreas Jung -
Chris McDonough -
Chris Withers -
David A. Riggs -
Toby Dickenson