Hi, I hope it’s OK to ask a question here (the About section said as much).
I’m receiving messages in the journal that I have difficulty interpreting. It appears to repeatedly switch from TCP to UDP and back, claiming that both are a “degraded feature set”…
Here is a sample journal output:
~$ journalctl --unit
systemd-resolved.service -r | head -n 60
May 02 10:29:56 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:29:56 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:29:46 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:29:46 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:29:46 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:29:46 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:29:46 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:29:46 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:27:50 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:27:50 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:27:33 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:27:33 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:27:19 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:27:19 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:27:16 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:27:16 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:26:53 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:26:53 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:26:39 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:26:39 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:26:38 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:26:38 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:26:36 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:26:36 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:25 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:25 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:24 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:24 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:24 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:24 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:24 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:24 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:25:23 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:22 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:25:22 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:24:55 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:24:55 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:24:51 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:24:51 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:24:51 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:24:51 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:24:48 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:24:48 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:24:48 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:24:35 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of UDP+EDNS0 for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:24:35 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of UDP+EDNS0 for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:23:54 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:23:54 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:23:54 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:23:54 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:23:54 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.1.1.1#cloudflare-dns.com.
May 02 10:22:56 nailbox systemd-resolved[95890]: Using
degraded feature set TCP instead of UDP for DNS server
1.0.0.1#cloudflare-dns.com.
May 02 10:22:56 nailbox systemd-resolved[95890]: Using
degraded feature set UDP instead of TCP for DNS server
1.0.0.1#cloudflare-dns.com.
Do you know if this is intended behavior? What am I supposed to make of this?
Here is my /etc/systemd/resolved.conf:
[Resolve]
DNS=1.1.1.1#cloudflare-dns.com 1.0.0.1#cloudflare-dns.com
2606:4700:4700::1111#cloudflare-dns.com
2606:4700:4700::1001#cloudflare-dns.com
LLMNR=true
DNSSEC=false
DNSOverTLS=false
Here is the output of resolvectl status
(with the local DNS redacted):
Global
Protocols: +LLMNR +mDNS -DNSOverTLS
DNSSEC=no/unsupported
resolv.conf mode: stub
Current DNS Server: 1.1.1.1#cloudflare-dns.com
DNS Servers: 1.1.1.1#cloudflare-dns.com
1.0.0.1#cloudflare-dns.com
2606:4700:4700::1111#cloudflare-dns.com
2606:4700:4700::1001#cloudflare-dns.com
Fallback DNS Servers: 1.1.1.1#cloudflare-dns.com
8.8.8.8#dns.google 1.0.0.1#cloudflare-dns.com
8.8.4.4#dns.google 2606:4700:4700::1111#cloudflare-dns.com
2001:4860:4860::8888#dns.google
2606:4700:4700::1001#cloudflare-dns.com
2001:4860:4860::8844#dns.google
Link 2 (docker0)
Current Scopes: none
Protocols: -DefaultRoute +LLMNR +mDNS -DNSOverTLS
DNSSEC=no/unsupported
Link 3 (wlp4s0)
Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6 mDNS/IPv4
mDNS/IPv6
Protocols: +DefaultRoute +LLMNR +mDNS -DNSOverTLS
DNSSEC=no/unsupported
Current DNS Server: ███████████████
DNS Servers: ███████████████
DNS Domain: intern
I’m using NixOS (24.05.20240425.7bb2ccd (Uakari)) and running
systemd 255.4. Here is the output of systemctl
--version:
systemd 255 (255.4)
+PAM +AUDIT -SELINUX +APPARMOR +IMA +SMACK +SECCOMP +GCRYPT
-GNUTLS +OPENSSL +ACL +BLKID +CURL +ELFUTILS +FIDO2 +IDN2 -IDN
+IPTC +KMOD +LIBCRYPTSETUP +LIBFDISK +PCRE2 +PWQUALITY +P11KIT
+QRENCODE +TPM2 +BZIP2 +LZ4 +XZ +ZLIB +ZSTD +BPF_FRAMEWORK
-XKBCOMMON +UTMP -SYSVINIT default-hierarchy=unified
Normally I have an Autocrypt header with PGP information but I
just set up this system and haven’t configured GPG/Thunderbird
with that yet.
Sincerely, Anselm Schüler (email, website)
