Why is dhclient + systemd-resolved restarting frequently?












0















I'm running an ubuntu server in aws on VERSION="18.10 (Cosmic Cuttlefish)"



We've been having intermittent dns resolution issues, and while looking into that I've seen that every 20 minutes or so I'm seeing the following in syslog



Mar 19 00:17:03 localhost dhclient[815]: DHCPREQUEST of 172.31.26.85 on eth0 to 172.31.16.1 port 67 (xid=0x7d329bb3)
Mar 19 00:17:03 localhost dhclient[815]: DHCPACK of 172.31.26.85 from 172.31.16.1
Mar 19 00:17:03 localhost systemd[1]: Stopping Network Name Resolution...
Mar 19 00:17:03 localhost systemd[1]: Stopped Network Name Resolution.
Mar 19 00:17:03 localhost systemd[1]: Starting Network Name Resolution...
Mar 19 00:17:04 localhost dhclient[815]: bound to 172.31.26.85 -- renewal in 1747 seconds.


It seems every time dhclient goes through a renewal process it causes systemd-resolved to restart, which momentarily makes dns resolution not work. So if some process was running at that time, the resolution may fail.



I'm not really sure where to begin on this. Is it normal for dhclient to cause systemd-resolved to restart so frequently? What's the right solution to this issue? Should I force dhclient to renew much less frequently, does that have some negative impact? Any other suggestions?










share|improve this question







New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
















  • 1





    "renewal in 1747 seconds" suggests maybe the network's DHCP server is configured to offer ~30 minute lease durations?

    – steeldriver
    1 hour ago
















0















I'm running an ubuntu server in aws on VERSION="18.10 (Cosmic Cuttlefish)"



We've been having intermittent dns resolution issues, and while looking into that I've seen that every 20 minutes or so I'm seeing the following in syslog



Mar 19 00:17:03 localhost dhclient[815]: DHCPREQUEST of 172.31.26.85 on eth0 to 172.31.16.1 port 67 (xid=0x7d329bb3)
Mar 19 00:17:03 localhost dhclient[815]: DHCPACK of 172.31.26.85 from 172.31.16.1
Mar 19 00:17:03 localhost systemd[1]: Stopping Network Name Resolution...
Mar 19 00:17:03 localhost systemd[1]: Stopped Network Name Resolution.
Mar 19 00:17:03 localhost systemd[1]: Starting Network Name Resolution...
Mar 19 00:17:04 localhost dhclient[815]: bound to 172.31.26.85 -- renewal in 1747 seconds.


It seems every time dhclient goes through a renewal process it causes systemd-resolved to restart, which momentarily makes dns resolution not work. So if some process was running at that time, the resolution may fail.



I'm not really sure where to begin on this. Is it normal for dhclient to cause systemd-resolved to restart so frequently? What's the right solution to this issue? Should I force dhclient to renew much less frequently, does that have some negative impact? Any other suggestions?










share|improve this question







New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
















  • 1





    "renewal in 1747 seconds" suggests maybe the network's DHCP server is configured to offer ~30 minute lease durations?

    – steeldriver
    1 hour ago














0












0








0








I'm running an ubuntu server in aws on VERSION="18.10 (Cosmic Cuttlefish)"



We've been having intermittent dns resolution issues, and while looking into that I've seen that every 20 minutes or so I'm seeing the following in syslog



Mar 19 00:17:03 localhost dhclient[815]: DHCPREQUEST of 172.31.26.85 on eth0 to 172.31.16.1 port 67 (xid=0x7d329bb3)
Mar 19 00:17:03 localhost dhclient[815]: DHCPACK of 172.31.26.85 from 172.31.16.1
Mar 19 00:17:03 localhost systemd[1]: Stopping Network Name Resolution...
Mar 19 00:17:03 localhost systemd[1]: Stopped Network Name Resolution.
Mar 19 00:17:03 localhost systemd[1]: Starting Network Name Resolution...
Mar 19 00:17:04 localhost dhclient[815]: bound to 172.31.26.85 -- renewal in 1747 seconds.


It seems every time dhclient goes through a renewal process it causes systemd-resolved to restart, which momentarily makes dns resolution not work. So if some process was running at that time, the resolution may fail.



I'm not really sure where to begin on this. Is it normal for dhclient to cause systemd-resolved to restart so frequently? What's the right solution to this issue? Should I force dhclient to renew much less frequently, does that have some negative impact? Any other suggestions?










share|improve this question







New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












I'm running an ubuntu server in aws on VERSION="18.10 (Cosmic Cuttlefish)"



We've been having intermittent dns resolution issues, and while looking into that I've seen that every 20 minutes or so I'm seeing the following in syslog



Mar 19 00:17:03 localhost dhclient[815]: DHCPREQUEST of 172.31.26.85 on eth0 to 172.31.16.1 port 67 (xid=0x7d329bb3)
Mar 19 00:17:03 localhost dhclient[815]: DHCPACK of 172.31.26.85 from 172.31.16.1
Mar 19 00:17:03 localhost systemd[1]: Stopping Network Name Resolution...
Mar 19 00:17:03 localhost systemd[1]: Stopped Network Name Resolution.
Mar 19 00:17:03 localhost systemd[1]: Starting Network Name Resolution...
Mar 19 00:17:04 localhost dhclient[815]: bound to 172.31.26.85 -- renewal in 1747 seconds.


It seems every time dhclient goes through a renewal process it causes systemd-resolved to restart, which momentarily makes dns resolution not work. So if some process was running at that time, the resolution may fail.



I'm not really sure where to begin on this. Is it normal for dhclient to cause systemd-resolved to restart so frequently? What's the right solution to this issue? Should I force dhclient to renew much less frequently, does that have some negative impact? Any other suggestions?







networking dns display-resolution dhcp systemd-resolved






share|improve this question







New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|improve this question







New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|improve this question




share|improve this question






New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked 1 hour ago









user3005200user3005200

1




1




New contributor




user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






user3005200 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.








  • 1





    "renewal in 1747 seconds" suggests maybe the network's DHCP server is configured to offer ~30 minute lease durations?

    – steeldriver
    1 hour ago














  • 1





    "renewal in 1747 seconds" suggests maybe the network's DHCP server is configured to offer ~30 minute lease durations?

    – steeldriver
    1 hour ago








1




1





"renewal in 1747 seconds" suggests maybe the network's DHCP server is configured to offer ~30 minute lease durations?

– steeldriver
1 hour ago





"renewal in 1747 seconds" suggests maybe the network's DHCP server is configured to offer ~30 minute lease durations?

– steeldriver
1 hour ago










0






active

oldest

votes











Your Answer








StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "89"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});






user3005200 is a new contributor. Be nice, and check out our Code of Conduct.










draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faskubuntu.com%2fquestions%2f1127069%2fwhy-is-dhclient-systemd-resolved-restarting-frequently%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes








user3005200 is a new contributor. Be nice, and check out our Code of Conduct.










draft saved

draft discarded


















user3005200 is a new contributor. Be nice, and check out our Code of Conduct.













user3005200 is a new contributor. Be nice, and check out our Code of Conduct.












user3005200 is a new contributor. Be nice, and check out our Code of Conduct.
















Thanks for contributing an answer to Ask Ubuntu!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faskubuntu.com%2fquestions%2f1127069%2fwhy-is-dhclient-systemd-resolved-restarting-frequently%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

GameSpot

日野市

Tu-95轟炸機