Hi Paul, Thank you. And, yes, I saw Chris' posting, but I don't think that's the right solution for us. A fast shared session variable store seems to me to be a better way to go and a whole lot more fail safe. On Tue, 3 May 2005, Paul Winkler wrote:

On Tue, May 03, 2005 at 05:14:56PM -0400, Tres Seaver wrote:

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Dennis Allison wrote:

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I am just setting up a multi-headed distributed system with several Zope heads all communications with a ZEO backend. The zopes can be on the same machine or on different machines connected through a high speed backbone. In our system, all zopes are frontended with pound.

zope1 | zope2----- ZEO-----zope3 | zope4

We make heavy use of session variables. Normally, with a single Zope session variables are stored in a temporary folder, but, as such, they are are not shared between the zope heads. In the multiheaded system, the session variables need to be shared and therefore must be managed by ZEO. What is the recommended best practice for this?

Richard Jones recently released a SQL-based sessioning implementation:

http://www.zope.org/Members/richard/ZSQLSessionDataManager

Or you could look through today's messages to this list, where I recall Chris McDonough mentioned using pound to force sessions to stick to a ZEO client. That's appealingly simple; the obvious drawback is that the session would be lost if the ZEO client restarts. Presumably details can be found in the pound docs.

-- Dennis Allison * Computer Systems Laboratory * Gates 227 * Stanford University * Stanford CA 94305 * (650) 723-9213 * (650) 723-0033 fax * allison@shasta.stanford.edu * allison@sumeru.stanford.edu