I confirmed this BUG under Win10 Pro 1803, os17134.191.
My host file is 2MB and each time when connect to internet must wait at least 1-2 minutes before to have active net!?!?!?!?
This is 100% bug in DNS Client when working with > 1M host file
Windows 10 DNSClient bug
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Anonymous
Hi, it seems that DNSClient is reloading the hosts file even if there are no changes to it. Especially when connecting or reconnecting to networks. This take over 5 minutes for a large hosts file, during which the computer does not connect to the internet and with high CPU usage for DNS Client.
Ideally the hosts file should be cached and persisted to disk between reboots and between network connections. Reloading should occur only when there are changes to the hosts file.
Windows for home | Windows 10 | Internet and connectivity
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4 answers
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Anonymous
2018-07-31T11:33:57+00:00 -
Anonymous
2018-06-26T18:02:04+00:00 There is no bug - it is doing exactly what it should do - combining dynamic, time limited data from server(s) with the static data from the hosts file on startup
The only data that could be 'persisted to disk between reboots' is the host file and it already exists as a file.
The question is why the host file is so big. This usually only occurs when it is misused in an attempt to stop normal DNS (server based) resolution.
The hosts file is only 2MB on my SSD drive contains thousands of unwanted/ad/unethical domains that needs to resolve to 0.0.0.0
Why do you not consider it as bug as its reloading the file each time the network changes or reboots, that is causing no network for several minutes. DNSClient seems to be way too slow, single threaded and parses host file unnecessarily? I have written programs to read such files that works in few seconds, whereas your implementation seems not to be as efficient taking over 15 mins to load a 2MB file from SSD storage.
If you are not willing to fix it, can you please guide us on how to write our own implementation of DNSClient that can run natively inside Windows?
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Anonymous
2018-07-14T18:29:00+00:00 Can you respond to fixing this issue please?
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Anonymous
2018-06-26T10:15:58+00:00 There is no bug - it is doing exactly what it should do - combining dynamic, time limited data from server(s) with the static data from the hosts file on startup
The only data that could be 'persisted to disk between reboots' is the host file and it already exists as a file.
The question is why the host file is so big. This usually only occurs when it is misused in an attempt to stop normal DNS (server based) resolution.