func (c *CoreDNS) String() string {
	return "etcdDNS"
}

// CoreDNS - represents dns config for coredns server.
type CoreDNS struct {
	domainNames []string
	domainIPs   set.StringSet
	domainPort  string
	prefixPath  string
	etcdClient  *clientv3.Client
}

// EtcdOption - functional options pattern style
type EtcdOption func(*CoreDNS)

### 2. Run MinIO in federated mode

Bucket lookup from DNS federation requires two dependencies

- etcd (for bucket DNS service records)
- CoreDNS (for DNS management based on populated bucket DNS service records, optional)

## Architecture

![bucket-lookup](https://github.com/minio/minio/blob/master/docs/federation/lookup/bucket-lookup.png?raw=true)

## Known Issues

- There is a known issue [coredns/coredns#2629](https://github.com/coredns/coredns/issues/2629) in CoreDNS 1.3.1, wherein if the Kubernetes API shuts down while CoreDNS is connected, CoreDNS will crash. The issue is fixed in CoreDNS 1.4.0 in [coredns/coredns#2529](https://github.com/coredns/coredns/pull/2529).

- Kubeadm: when using a custom image repository for CoreDNS kubeadm now will append the `coredns` image name instead of `coredns/coredns`, thus restoring the behaviour existing before the v1.21 release. Users who rely on nested folder for the coredns image should set the `clusterConfiguration.dns.imageRepository` value including the nested path name (e.g using `registry.company.xyz/coredns` will force kubeadm to use `registry.company.xyz/coredns/coredns` image). No action is needed if using the default...

- ACTION REQUIRED : In CoreDNS v1.7.0, [metrics names have been changed](https://github.com/coredns/coredns/blob/master/notes/coredns-1.7.0.md#metric-changes) which will be backward incompatible with existing reporting formulas that use the old metrics' names. Adjust your formulas to the new names before upgrading. 
  
  Kubeadm now includes CoreDNS version v1.7.0. Some of the major changes include:

- CoreDNS correctly implements DNS spec for Services with externalNames that look like IP addresses. Kube-dns does not follow the spec for the same case, resulting in a behavior change when moving from Kube-dns to CoreDNS. See: [coredns/coredns#2324](https://github.com/coredns/coredns/issues/2324)

- Upgrade CoreDNS to v1.12.4 ([#133968](https://github.com/kubernetes/kubernetes/pull/133968), [@yashsingh74](https://github.com/yashsingh74)) [SIG Cloud Provider and Cluster Lifecycle]

## Dependencies

### Added
- cyphar.com/go-pathrs: v0.2.1

### Changed
- github.com/coredns/corefile-migration: [v1.0.27 → v1.0.29](https://github.com/coredns/corefile-migration/compare/v1.0.27...v1.0.29)

- This renames some coredns metrics, see https://github.com/coredns/coredns/blob/v1.11.0/plugin/forward/README.md#metrics. ([#129175](https://github.com/kubernetes/kubernetes/pull/129175), [@DamianSawicki](https://github.com/DamianSawicki)) [SIG Cloud Provider]

### Feature

- ACTION REQUIRED : In CoreDNS v1.7.0, [metrics names have been changed](https://github.com/coredns/coredns/blob/master/notes/coredns-1.7.0.md#metric-changes) which will be backward incompatible with existing reporting formulas that use the old metrics' names. Adjust your formulas to the new names before upgrading. 
  
  Kubeadm now includes CoreDNS version v1.7.0. Some of the major changes include:

### SIG Network

The main milestones for SIG Network this release are the graduation of IPVS-based load balancing and CoreDNS to general availability.

IPVS is an alternative approach to in-cluster load balancing that uses in-kernel hash tables rather than the previous iptables approach, while CoreDNS is a replacement for kube-dns for service discovery.

### SIG Node