Fixes an issue reported by @klauspost and @vadmeste
This PR also allows users to expand their clusters
from single node XL deployment to distributed mode.
On Kubernetes/Docker setups DNS resolves inappropriately
sometimes where there are situations same endpoints with
multiple disks come online indicating either one of them
is local and some of them are not local. This situation
can never happen and its only a possibility in orchestrated
deployments with dynamic DNS. Following code ensures that we
treat if one of the endpoint says its local for a given host
it is true for all endpoints for the same host. Following code
ensures that this assumption is true and it works in all
scenarios and it is safe to assume for a given host.
This PR also adds validation such that we do not crash the
server if there are bugs in the endpoints list in dsync
initialization.
Thanks to Daniel Valdivia <hola@danielvaldivia.com> for
reproducing this, this fix is needed as part of the
https://github.com/minio/m3 project.
When checking if federation is necessary, the code compares
the SRV record stored in etcd against the list of endpoints
that the MinIO server is exposing. If there is an intersection
in this list the request is forwarded.
The SRV record includes both the host and the port, but the
intersection check previously only looked at the IP address. This
would prevent federation from working in situations where the endpoint
IP is the same for multiple MinIO servers. Some examples of where this
can occur are:
- running mulitiple copies of MinIO on the same host
- using multiple MinIO servers behind a NAT with port-forwarding
Allow server to start if one of the local nodes in docker/kubernetes setup is successfully resolved
- The rule is that we need atleast one local node to work. We dont need to resolve the
rest at that point.
- In a non-orchestrational setup, we fail if we do not have atleast one local node up
and running.
- In an orchestrational setup (docker-swarm and kubernetes), We retry with a sleep of 5
seconds until any one local node shows up.
Fixes#6995
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
Currently minio master requires 4 servers, we
have decided to run on a minimum of 2 servers
instead - fixes a regression from previous
releases where 3 server setups were supported.
When running `make test` in docker, two test cases cause hanging.
This Patch fixes the problem by removing those test cases.
Thanks to @ws141 for identifying the problem.
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
Harshavardhana