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TheOn my router, for my home network, on my router in the DHCP server settings, I specified the primary and secondary DNS servers as (8.8.8.88.8.8.8, 8.8.4.4)8.8.4.4. On the home server is installedI have Ubuntu 16.04.4 LTS forinstalled on my home server. For network management I use NeteorkManager, with included dnsmasq. The /etc/resolv.conf/etc/resolv.conf file contains: nameserver 127.0.1.1nameserver 127.0.1.1

I noticed such a featurethat, if I request a dns entry, then the Ubuntu sends two requests simultaneously to the primary and secondary dns server.

Send query:

nslookup ya.ru

Information from tcpdump:

19: 07: 53.596844 IP 192.168.100.14.38814> 8.8.8.8.53: 41973+ A? ya.ru. (23)
19: 07: 53.596853 IP 192.168.100.14.38814> 8.8.4.4.53: 41973+ A? ya.ru. (23)
19: 07: 53.600385 IP 8.8.8.8.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)
19: 07: 53.615338 IP 8.8.4.4.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)

Why does the system send two requests at once? And what do I need to change so that it would behave logically and send a request to the secondary DNS server only when there is no response from the Primary DNS server.

The home network, on my router in the DHCP server settings, I specified the primary and secondary DNS servers (8.8.8.8, 8.8.4.4). On the home server is installed Ubuntu 16.04.4 LTS for network management I use NeteorkManager with included dnsmasq. The /etc/resolv.conf file contains: nameserver 127.0.1.1

I noticed such a feature, if I request a dns entry, then the Ubuntu sends two requests simultaneously to the primary and secondary dns server.

Send query:

nslookup ya.ru

Information from tcpdump:

19: 07: 53.596844 IP 192.168.100.14.38814> 8.8.8.8.53: 41973+ A? ya.ru. (23)
19: 07: 53.596853 IP 192.168.100.14.38814> 8.8.4.4.53: 41973+ A? ya.ru. (23)
19: 07: 53.600385 IP 8.8.8.8.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)
19: 07: 53.615338 IP 8.8.4.4.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)

Why does the system send two requests at once? And what to change that it would behave logically and send a request to the secondary DNS server only when there is no response from the Primary DNS server.

On my router, for my home network, in the DHCP server settings, I specified the primary and secondary DNS servers as 8.8.8.8, 8.8.4.4. I have Ubuntu 16.04.4 LTS installed on my home server. For network management I use NeteorkManager, with included dnsmasq. The /etc/resolv.conf file contains: nameserver 127.0.1.1

I noticed that, if I request a dns entry, then the Ubuntu sends two requests simultaneously to the primary and secondary dns server.

Send query:

nslookup ya.ru

Information from tcpdump:

19: 07: 53.596844 IP 192.168.100.14.38814> 8.8.8.8.53: 41973+ A? ya.ru. (23)
19: 07: 53.596853 IP 192.168.100.14.38814> 8.8.4.4.53: 41973+ A? ya.ru. (23)
19: 07: 53.600385 IP 8.8.8.8.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)
19: 07: 53.615338 IP 8.8.4.4.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)

Why does the system send two requests at once? And what do I need to change so that it would behave logically and send a request to the secondary DNS server only when there is no response from the Primary DNS server.

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Repeated DNS query on Ubuntu

The home network, on my router in the DHCP server settings, I specified the primary and secondary DNS servers (8.8.8.8, 8.8.4.4). On the home server is installed Ubuntu 16.04.4 LTS for network management I use NeteorkManager with included dnsmasq. The /etc/resolv.conf file contains: nameserver 127.0.1.1

I noticed such a feature, if I request a dns entry, then the Ubuntu sends two requests simultaneously to the primary and secondary dns server.

Send query:

nslookup ya.ru

Information from tcpdump:

19: 07: 53.596844 IP 192.168.100.14.38814> 8.8.8.8.53: 41973+ A? ya.ru. (23)
19: 07: 53.596853 IP 192.168.100.14.38814> 8.8.4.4.53: 41973+ A? ya.ru. (23)
19: 07: 53.600385 IP 8.8.8.8.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)
19: 07: 53.615338 IP 8.8.4.4.53> 192.168.100.14.38814: 41973 1/0/0 A 87.250.250.242 (39)

Why does the system send two requests at once? And what to change that it would behave logically and send a request to the secondary DNS server only when there is no response from the Primary DNS server.