Натура Антон, 3530901/70201

[antoshka77]

Вторая лабораторная, отчёт находится в lab2/README.md.

[wrbbz]

• DNS - зачет
• NTP. При попытке запроса времени у сервера, сервер выплевывает исключения. В отчете можно описать как проводилось тестирование сервера. Например, запуск сервера, с такими-то аргументами. И на сервер кидаются запросы такого-то формата.
  Сейчас:

Клиент:

➜ ntpq -c 'rv 0 clock' localhost
localhost: timed out, nothing received
***Request timed out

Сервер:

> Task :lab2-ntp-server:run
18:59:42.813 [DefaultDispatcher-worker-3] INFO com.github.antoshka77.inet.dns.Server - incoming datagram from /0:0:0:0:0:0:0:1:45739
18:59:42.828 [DefaultDispatcher-worker-3] ERROR com.github.antoshka77.inet.dns.Server - ntp format error: Premature end of stream: expected 4 bytes
18:59:42.837 [DefaultDispatcher-worker-3] INFO com.github.antoshka77.inet.dns.Server - sent error: Packet(leap=NoWarning, version=4, mode=Server, stratum=com.github.antoshka77.inet.ntp.Packet$Stratum$Unspecified@348062d6, poll=0, precision=0, rootDelay=NTPTime(seconds=0, fraction=0), rootDispersion=NTPTime(seconds=1, fraction=0), referenceId=DENY, originTimestamp=NTPTime(seconds=0, fraction=0), receiveTimestamp=NTPTime(seconds=0, fraction=0), transmitTimestamp=NTPTime(seconds=0, fraction=0), destinationTimestamp=NTPTime(seconds=0, fraction=0))
java.io.EOFException: Premature end of stream: expected 4 bytes
        at io.ktor.utils.io.core.StringsKt.prematureEndOfStream(Strings.kt:481)
        at io.ktor.utils.io.core.InputPrimitivesKt.readIntFallback(InputPrimitives.kt:86)
        at io.ktor.utils.io.core.InputPrimitivesKt.readInt(InputPrimitives.kt:17)
        at com.github.antoshka77.inet.ntp.NTPTimeKt.readNTPTimestamp(NTPTime.kt:28)
        at com.github.antoshka77.inet.ntp.Packet$Companion.decode(Packet.kt:95)
        at com.github.antoshka77.inet.dns.ServerKt.main(Server.kt:58)
        at com.github.antoshka77.inet.dns.ServerKt$main$1.invokeSuspend(Server.kt)
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
        at kotlinx.coroutines.DispatchedTaskKt.resume(DispatchedTask.kt:178)
        at kotlinx.coroutines.DispatchedTaskKt.dispatch(DispatchedTask.kt:166)
        at kotlinx.coroutines.CancellableContinuationImpl.dispatchResume(CancellableContinuationImpl.kt:362)
        at kotlinx.coroutines.CancellableContinuationImpl.completeResume(CancellableContinuationImpl.kt:479)
        at kotlinx.coroutines.channels.AbstractChannel$ReceiveElement.completeResumeReceive(AbstractChannel.kt:899)
        at kotlinx.coroutines.channels.AbstractSendChannel.offerInternal(AbstractChannel.kt:56)
        at kotlinx.coroutines.channels.AbstractSendChannel.send(AbstractChannel.kt:135)
        at kotlinx.coroutines.channels.ChannelCoroutine.send$suspendImpl(ChannelCoroutine.kt)
        at kotlinx.coroutines.channels.ChannelCoroutine.send(ChannelCoroutine.kt)
        at io.ktor.network.sockets.DatagramSocketImpl$receiver$1.invokeSuspend(DatagramSocketImpl.kt:41)
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
        at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
        at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:571)
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:738)
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:678)
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:665)
18:59:47.844 [DefaultDispatcher-worker-1] INFO com.github.antoshka77.inet.dns.Server - incoming datagram from /0:0:0:0:0:0:0:1:45739
18:59:47.845 [DefaultDispatcher-worker-1] ERROR com.github.antoshka77.inet.dns.Server - ntp format error: Premature end of stream: expected 4 bytes
18:59:47.848 [DefaultDispatcher-worker-1] INFO com.github.antoshka77.inet.dns.Server - sent error: Packet(leap=NoWarning, version=4, mode=Server, stratum=com.github.antoshka77.inet.ntp.Packet$Stratum$Unspecified@348062d6, poll=0, precision=0, rootDelay=NTPTime(seconds=0, fraction=0), rootDispersion=NTPTime(seconds=1, fraction=0), referenceId=DENY, originTimestamp=NTPTime(seconds=0, fraction=0), receiveTimestamp=NTPTime(seconds=0, fraction=0), transmitTimestamp=NTPTime(seconds=0, fraction=0), destinationTimestamp=NTPTime(seconds=0, fraction=0))
java.io.EOFException: Premature end of stream: expected 4 bytes
        at io.ktor.utils.io.core.StringsKt.prematureEndOfStream(Strings.kt:481)
        at io.ktor.utils.io.core.InputPrimitivesKt.readIntFallback(InputPrimitives.kt:86)
        at io.ktor.utils.io.core.InputPrimitivesKt.readInt(InputPrimitives.kt:17)
        at com.github.antoshka77.inet.ntp.NTPTimeKt.readNTPTimestamp(NTPTime.kt:28)
        at com.github.antoshka77.inet.ntp.Packet$Companion.decode(Packet.kt:95)
        at com.github.antoshka77.inet.dns.ServerKt.main(Server.kt:58)
        at com.github.antoshka77.inet.dns.ServerKt$main$1.invokeSuspend(Server.kt)
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
        at kotlinx.coroutines.DispatchedTaskKt.resume(DispatchedTask.kt:178)
        at kotlinx.coroutines.DispatchedTaskKt.dispatch(DispatchedTask.kt:166)
        at kotlinx.coroutines.CancellableContinuationImpl.dispatchResume(CancellableContinuationImpl.kt:362)
        at kotlinx.coroutines.CancellableContinuationImpl.completeResume(CancellableContinuationImpl.kt:479)
        at kotlinx.coroutines.channels.AbstractChannel$ReceiveElement.completeResumeReceive(AbstractChannel.kt:899)
        at kotlinx.coroutines.channels.AbstractSendChannel.offerInternal(AbstractChannel.kt:56)
        at kotlinx.coroutines.channels.AbstractSendChannel.send(AbstractChannel.kt:135)
        at kotlinx.coroutines.channels.ChannelCoroutine.send$suspendImpl(ChannelCoroutine.kt)
        at kotlinx.coroutines.channels.ChannelCoroutine.send(ChannelCoroutine.kt)
        at io.ktor.network.sockets.DatagramSocketImpl$receiver$1.invokeSuspend(DatagramSocketImpl.kt:41)
        at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
        at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
        at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:571)
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:738)
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:678)
        at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:665)

[antoshka77]

Для тестирования я пытался найти клиент попроще чем системный ntp демон. Нашёл далеко не самый лучший вариант https://github.com/lettier/ntpclient. Можно попробовать доработать и тестировать с помощью ntpq, но меня смущает то, что ntpq при таком же запросе не смогла получить ответ от сервера 0.ru.pool.ntp.org. При этом то, с помощью чего я тестировал свой сервер, получает ответ от 0.ru.pool.ntp.org.

> ntpq -c 'rv 0 clock' 0.ru.pool.ntp.org
0.ru.pool.ntp.org: timed out, nothing received
***Request timed out
> ./ntpclient.py # host = "0.ru.pool.ntp.org"
Time = Mon Jan 11 05:56:48 2021

Я не уверен, что дальше делать.

[wrbbz]

Тестирование с другими клиентами дало положительный результат.
Моя ошибка.

А описание тестирования, которое ты делал, можно в отчет добавить. Лишним не будет.

Зачтено