Manual:$wgDefaultExternalStore

Details
The place to put new revisions, false to put them in the local text table.

Part of a URL, e.g.

Can be an array instead of a single string, to enable data distribution. A cluster will be chosen randomly each time from the array. If inserting on the selected cluster fails, another one will be tried until all clusters fail.

Keys must be consecutive integers, starting at zero.

Example: