## Architecture

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

### Environment variables

#### MINIO_ETCD_ENDPOINTS

This is comma separated list of etcd servers that you want to use as the MinIO federation back-end. This should
be same across the federated deployment, i.e. all the MinIO instances within a federated deployment should use same
etcd back-end.

      --log_caller: Comma-separated list of scopes for which to include caller information, scopes can be any of \[.*\]
      --log_output_level: Comma-separated minimum per-scope logging level of messages to output, in the form of <scope>:<level>,<scope>:<level>,... where scope can be one of \[.*\] and level can be one of \[.*\]

claim_name    (string)    JWT canned policy claim name, defaults to "policy"
claim_prefix  (string)    JWT claim namespace prefix e.g. "customer1/"
scopes        (csv)       Comma separated list of OpenID scopes for server, defaults to advertised scopes from discovery document e.g. "email,admin"
comment       (sentence)  optionally add a comment to this setting
```

and ENV based options

```

import java.util.regex.Pattern;

/**
 * Utility class for parsing CSV text
 */
public final class KuromojiCSVUtil {
    private static final char QUOTE = '"';

    private static final char COMMA = ',';

    private static final Pattern QUOTE_REPLACE_PATTERN = Pattern.compile("^\"([^\"]+)\"$");

    private static final String ESCAPED_QUOTE = "\"\"";

    private KuromojiCSVUtil() {
    } // no instance!!!

      - prefix(istio.io/) # Groups all imports with the specified Prefix.
  goimports:
    # put imports beginning with prefix after 3rd-party packages;
    # it's a comma-separated list of prefixes
    local-prefixes: istio.io/
issues:
  # Which dirs to exclude: issues from them won't be reported.
  # Can use regexp here: `generated.*`, regexp is applied on full path,

```
KEY:
etcd  federate multiple clusters for IAM and Bucket DNS

ARGS:
endpoints*       (csv)       comma separated list of etcd endpoints e.g. "http://localhost:2379"
path_prefix      (path)      namespace prefix to isolate tenants e.g. "customer1/"
coredns_path     (path)      shared bucket DNS records, default is "/skydns"

claim_name    (string)    JWT canned policy claim name, defaults to "policy"
claim_prefix  (string)    JWT claim namespace prefix e.g. "customer1/"
scopes        (csv)       Comma separated list of OpenID scopes for server, defaults to advertised scopes from discovery document e.g. "email,admin"
comment       (sentence)  optionally add a comment to this setting
```

and ENV based options

```

	// operatorNamespace is the namespace the operator controller is installed into.
	operatorNamespace string
	// watchedNamespaces is the namespaces the operator controller watches, could be namespace list separated by comma.
	watchedNamespaces string
	// istioNamespace is deprecated, use watchedNamespaces instead.
	istioNamespace string
	// manifestsPath is a path to a charts and profiles directory in the local filesystem with a release tgz.

  std::set<string> factories_sorted;
  for (const auto& factory : GetFactories())
    factories_sorted.insert(factory.first);
  const char* comma = "";
  for (const string& factory : factories_sorted) {
    msg += comma + factory;
    comma = ", ";
  }
  msg += ")";

  return errors::InvalidArgument(msg.c_str());
}

static TracingContext* CreateTracingExecutionContext(const char* fn_name,

var (
	defaultHelpPostfix = func(key string) string {
		return config.DefaultHelpPostfix(DefaultKVS, key)
	}

	Help = config.HelpKVS{
		config.HelpKV{
			Key:         Endpoints,
			Description: `comma separated list of etcd endpoints` + defaultHelpPostfix(Endpoints),
			Type:        "csv",
			Sensitive:   true,
		},
		config.HelpKV{
			Key:         PathPrefix,