Intermittent DNS errors that prevent web page loading, etc. nslookup shows
nslookup r.bing.com
;; communications error to 127.0.0.53#53: timed out
;; communications error to 127.0.0.53#53: timed out
;; communications error to 127.0.0.53#53: timed out
;; no servers could be reached
127.0.0.53 is systemd's DNS server. That goes out to the local AT&T fibre, which goes to Sonic.net. DNS is all the ISP default.
Setup is vanilla 22.04 LTS. No manual changes to DNS config. This problem is occurring on two desktop machines, side by side on the same LAN.
This has become much worse since the last update to Ubuntu 22.04 LTS about two days ago.
Internet connection is wired 1GB Ethernet -> AT&T U-Verse fiber modem - AT&T fiber -> Sonic.net (which uses AT&T for the last mile.)
Systemd's report from the last boot:
That looks OK.
This is an intermittent failure. Try once, it may fail. Try 10 times, and it almost always succeeds.
If I set nslookup to use 192.168.1.254 as the DNS server (the same server systemd is supposedly using, connections via systemd fail while connections to the DNS server in the AT&T UVerse box work.
So this looks like some kind of systemd problem.
Setting an explicit DNS server IP address in the "Settings" GUI for IPv4 seems to have no effect.
Manually hacking that file has been suggested in other forums, but that's a desperation measure.
There is no "systemd-resolve" installed.
nslookup r.bing.com
;; communications error to 127.0.0.53#53: timed out
;; communications error to 127.0.0.53#53: timed out
;; communications error to 127.0.0.53#53: timed out
;; no servers could be reached
127.0.0.53 is systemd's DNS server. That goes out to the local AT&T fibre, which goes to Sonic.net. DNS is all the ISP default.
Setup is vanilla 22.04 LTS. No manual changes to DNS config. This problem is occurring on two desktop machines, side by side on the same LAN.
This has become much worse since the last update to Ubuntu 22.04 LTS about two days ago.
Internet connection is wired 1GB Ethernet -> AT&T U-Verse fiber modem - AT&T fiber -> Sonic.net (which uses AT&T for the last mile.)
Systemd's report from the last boot:
Code:
journalctl -u systemd-resolved -f
Jul 21 13:29:47 Nagle-LTS systemd[1]: systemd-resolved.service: Consumed 5.977s CPU time.
-- Boot 975d9f133cfc41fda55952df737f5c53 --
Jul 21 13:30:30 Nagle-LTS systemd[1]: Starting Network Name Resolution...
Jul 21 13:30:31 Nagle-LTS systemd-resolved[900]: Positive Trust Anchors:
Jul 21 13:30:31 Nagle-LTS systemd-resolved[900]: . IN DS 20326 8 2 e06d44b80b8f1d39a95c0b0d7c65d08458e880409bbc683457104237c7f8ec8d
Jul 21 13:30:31 Nagle-LTS systemd-resolved[900]: Negative trust anchors: home.arpa 10.in-addr.arpa 16.172.in-addr.arpa 17.172.in-addr.arpa 18.172.in-addr.arpa 19.172.in-addr.arpa 20.172.in-addr.arpa 21.172.in-addr.arpa 22.172.in-addr.arpa 23.172.in-addr.arpa 24.172.in-addr.arpa 25.172.in-addr.arpa 26.172.in-addr.arpa 27.172.in-addr.arpa 28.172.in-addr.arpa 29.172.in-addr.arpa 30.172.in-addr.arpa 31.172.in-addr.arpa 168.192.in-addr.arpa d.f.ip6.arpa corp home internal intranet lan local private test
Jul 21 13:30:31 Nagle-LTS systemd-resolved[900]: Using system hostname 'Nagle-LTS'.
Jul 21 13:30:31 Nagle-LTS systemd[1]: Started Network Name Resolution.
Jul 21 13:30:50 Nagle-LTS systemd-resolved[900]: enp3s0: Bus client set search domain list to: attlocal.net, attlocal.net
Jul 21 13:30:50 Nagle-LTS systemd-resolved[900]: enp3s0: Bus client set default route setting: yes
Jul 21 13:30:50 Nagle-LTS systemd-resolved[900]: enp3s0: Bus client set DNS server list to: 192.168.1.254, 2600:1700:22f6:2410::1That looks OK.
This is an intermittent failure. Try once, it may fail. Try 10 times, and it almost always succeeds.
If I set nslookup to use 192.168.1.254 as the DNS server (the same server systemd is supposedly using, connections via systemd fail while connections to the DNS server in the AT&T UVerse box work.
So this looks like some kind of systemd problem.
Setting an explicit DNS server IP address in the "Settings" GUI for IPv4 seems to have no effect.
Code:
/etc/resolv.conf reads
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
# 127.0.0.53 is the systemd-resolved stub resolver.
# run "systemd-resolve --status" to see details about the actual nameservers.
nameserver 127.0.0.53
search attlocal.netThere is no "systemd-resolve" installed.