This PR implements an object layer which
combines input erasure sets of XL layers
into a unified namespace.
This object layer extends the existing
erasure coded implementation, it is assumed
in this design that providing > 16 disks is
a static configuration as well i.e if you started
the setup with 32 disks with 4 sets 8 disks per
pack then you would need to provide 4 sets always.
Some design details and restrictions:
- Objects are distributed using consistent ordering
to a unique erasure coded layer.
- Each pack has its own dsync so locks are synchronized
properly at pack (erasure layer).
- Each pack still has a maximum of 16 disks
requirement, you can start with multiple
such sets statically.
- Static sets set of disks and cannot be
changed, there is no elastic expansion allowed.
- Static sets set of disks and cannot be
changed, there is no elastic removal allowed.
- ListObjects() across sets can be noticeably
slower since List happens on all servers,
and is merged at this sets layer.
Fixes#5465Fixes#5464Fixes#5461Fixes#5460Fixes#5459Fixes#5458Fixes#5460Fixes#5488Fixes#5489Fixes#5497Fixes#5496
Wait for remote hosts to resolve instead of failing on first host
resolution error, when running in Kubernetes or Docker environment.
Note that
- Waiting is based on exponential back-off mechanism
- If run as a binary, server fails if remote host is not resolvable
This is needed because in orchestration platforms like Kubernetes, remote
hosts are started sequentially and all the hosts are not up initially,
though they are expected to come up in a short time frame
It is difficult to identify a cap on the waiting time due to
non-deterministic nature of infrastructure platforms, so the server waits
infinitely for the hosts to come up, while logging the error messages to
the console.
Fixes: https://github.com/minio/minio/issues/4669
It is possible at times due to a typo when distributed mode was intended
a user might end up starting standalone erasure mode causing confusion.
Add code to check this based on some standard heuristic guess work and
report an error to the user.
Fixes#4686
