Cloned from launchpad blueprint https://blueprints.launchpad.net/oslo/+spec/db-reconnect.

Description:

There are a variety of circumstances which can cause a transient failure in database connections, for example:
- restart / upgrade of the database,
- migration of VIP between HA pair,
- just a network failure
- and so on.

All projects, connected to a database, would benefit from the db/api catching these "db-has-gone-away" errors and automatically reconnecting and retrying the last operation, in such a way that the caller is able to continue what ever operation was in process.

It is not necessary to abort long-running operations (such as nova boot or glance image-create) just because of a momentary interruption in db connectivity.

A (slightly brute-force) patch was previously proposed to Nova: https://review.openstack.org/#/c/10797/

Current bp is similar to Nova blueprint, proposed by Devananda van der Veen. See https://blueprints.launchpad.net/nova/+spec/db-reconnect

Specification URL (additional information):

None