///

### DNS { #dns }

Теперь сфокусируемся на собственно частях, связанных с HTTPS.

Сначала браузер спросит у **DNS‑серверов**, какой **IP соответствует домену**, в нашем примере `someapp.example.com`.

DNS‑серверы ответят браузеру, какой **конкретный IP‑адрес** использовать. Это будет публичный IP‑адрес вашего сервера, который вы указали в настройках DNS.

        .addSubjectAlternativeName("differentdns.com")
        .build()
    serverIps = Dns.SYSTEM.lookup(server.hostName)
    dns[server.hostName] = serverIps
    dns["san.com"] = serverIps
    dns["nonsan.com"] = serverIps
    dns["www.wildcard.com"] = serverIps
    dns["differentdns.com"] = listOf()
    val handshakeCertificates =
      HandshakeCertificates
        .Builder()

import java.net.InetAddress
import java.net.UnknownHostException
import okhttp3.Dns

/**
 * Internal Bootstrap DNS implementation for handling initial connection to DNS over HTTPS server.
 *
 * Returns hardcoded results for the known host.
 */
internal class BootstrapDns(
  private val dnsHostname: String,
  private val dnsServers: List<InetAddress>,
) : Dns {
  @Throws(UnknownHostException::class)

    object DnsOverride : Override<Dns> {
      override fun Interceptor.Chain.value(): Dns = dns

      override fun Interceptor.Chain.withOverride(value: Dns): Interceptor.Chain = withDns(value)

      override fun OkHttpClient.Builder.withOverride(value: Dns): OkHttpClient.Builder = dns(value)

      override val nonDefaultValue: Dns = Dns { Dns.SYSTEM.lookup(it) }

// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package dns

// Error - DNS related errors error.
type Error struct {
	Bucket string
	Err    error
}

// ErrInvalidBucketName for buckets with invalid name
type ErrInvalidBucketName Error

...
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseHeadersEnd: Response{protocol=h2, code=200, message=, url=https://1.1.1.1/dns-query?dns=AAABAAABAAAAAAAAA3d3dwhmYWNlYm9vawNjb20AABwAAQ}
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseBodyStart
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseBodyEnd: byteCount=128

...
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseHeadersEnd: Response{protocol=h2, code=200, message=, url=https://1.1.1.1/dns-query?dns=AAABAAABAAAAAAAAA3d3dwhmYWNlYm9vawNjb20AABwAAQ}
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseBodyStart
01-01 12:53:32.811 10999 11089 D OkHttp  : [49 ms] responseBodyEnd: byteCount=128

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package dns

import (
	"path"
	"strings"

	"github.com/miekg/dns"
)

// msgPath converts a domainname to an etcd path. If s looks like service.staging.skydns.local.,
// the resulting key will be /skydns/local/skydns/staging/service .
func msgPath(s, prefix string) string {
	l := dns.SplitDomainName(s)
	for i, j := 0, len(l)-1; i < j; i, j = i+1, j-1 {

	}
	if err == nil && dnsURL != "" {
		bootstrapTraceMsg("initialize remote bucket DNS store")
		globalDNSConfig, err = dns.NewOperatorDNS(dnsURL,
			dns.Authentication(dnsUser, dnsPass),
			dns.RootCAs(globalRootCAs))
		if err != nil {
			configLogIf(ctx, fmt.Errorf("Unable to initialize remote webhook DNS config %w", err))
		}
	}

///

### DNS { #dns }

Тепер зосередьмося на всіх власне частинах HTTPS.

Спочатку браузер звернеться до **DNS-серверів**, щоб дізнатися, яка **IP-адреса для домену**, у цьому випадку `someapp.example.com`.

Сервери DNS повідомлять браузеру використати конкретну **IP-адресу**. Це буде публічна IP-адреса, яку використовує ваш сервер і яку ви налаштували на серверах DNS.