Hi, Kevin,
Thanks for the KIP. A few comments.
JR1. ClusterIdRecord : Could you define the record format?
JR2. "a new MetadataVersion that supports encoding/decoding this record.
This means that during formatting, the bootstrap ClusterIdRecord is only
written if the cluster is formatted with a MV that supports this feature."
Could you describe who writes the ClusterIdRecord? Is it the leader
controller? Also, when is the record written? Do we guarantee that MV is
available at that time?
JR3. "meta.properties can be written during kafka broker/controller startup
if it doesn't exist already (from formatting)"
Could you describe when meta.properties is written? Is MV available at that
time?
JR4. "Introduce a metadata record for cluster id + observers persist
cluster id to meta.properties from metadata publishing pipeline"
Could you clarify what observers are? Are they observer controllers or are
they brokers (which are referred to as observers to the controller)?
JR5. "Bootstrap controllers can add a mandatory “cluster id” record during
formatting"
This sounds like adding a ClusterIdRecord is optional. If so, could you
describe when a record will be added and when a record will not be added?
JR6. "However, kafka should still be able to handle the case where a leader
is elected without a cluster id in meta.properties , since KRaft does not
need cluster.id in order to elect a leader.
In this case, the active controller will write a cluster id
record during the bootstrap metadata write."
Hmm, earlier, the KIP says "Upon discovering the cluster ID for the first
time, these nodes need to persist this to meta.properties". Why do we need
to introduce a separate place to write the cluster id to meta.properties.
Jun
On Wed, Feb 11, 2026 at 10:21 AM Kevin Wu <[email protected]> wrote:
> Hi all,
>
> Manually bumping this thread after finalizing a design.
> KIP link:
>
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-1262%3A+Enable+auto-formatting+directories
>
> Best,
> Kevin Wu
>
> On Tue, Jan 6, 2026 at 7:18 AM Kevin Wu <[email protected]> wrote:
>
> > Hello all,
> >
> > I would like to start a discussion on KIP-1262, which proposes removing
> > the formatting requirement for brokers and observer controllers.
> Currently,
> > I am considering two high-level designs, and would appreciate community
> > feedback on both approaches to decide on a final design.
> >
> > KIP link:
> >
> https://cwiki.apache.org/confluence/display/KAFKA/KIP-1262%3A+Enable+auto-formatting+directories
> >
> > Best,
> > Kevin Wu
> >
>
