On Thu, Feb 1, 2018 at 2:22 PM Enrico Olivelli <eolive...@gmail.com> wrote:
> Il gio 1 feb 2018, 22:43 Ivan Kelly <iv...@apache.org> ha scritto: > > > > well I don't think it is an easy effort to upgrade from flat ledger > > manager > > > to hierarchical ledger manager. There was a huge long discussion about > > this > > > migration 2-3 years ago. > > > > I remember one of my first questions as an user was about migrating away > from FlatLM. We did not finish and so for some cases my customers decided > to nuke the cluster and start a new one. > > > > Do you recall where the discussion was? JIRA or ML? Superficially it > > seems like a simple operation if the cluster is taken down while it is > > happening. > > > > Sijie, > I have tens of running BK clusters of my customers which are using FlatLM > because it is the default. Most of them are very little clusters with 3 > bookies. > > So I am ok with this move but I need a tool to migrate. We will not remove this class. But the default value will be flipped to hierarchical. We will provide the tool if we decide to drop it in future. But probably not at this moment. If anyone in the community has the time to work on this, it would be great as well! > > Having the full cluster down can be a option for my cases so I think my > customers will be happy even with a simple tool. > > Maybe we can have a tool which creates a new structure using a different > base path so that is case of failure the cluster is not compromised. Yes if downtime is acceptable, the solution will be easy, otherwise it is going to be very complicated to support live migration. Sijie > > Enrico > > > > -Ivan > > > > > -- > > > -- Enrico Olivelli >
