On 6/28/25 6:29 AM, Andy Pieters wrote:
On Sat, 28 Jun 2025 at 09:18, David C Rankin <[email protected]
<mailto:[email protected]>> wrote:
All,
I have my Arch server that has been running for a decade, updates
weekly, never misses a beat. It has been so long since I've had an
issue
with it, I thought Arch had finally reached Linux rolling release
nirvana.
Then, for reasons I can't explain, the update tonight
Whilst we wait for other insight, can we assume that you run pacdiff
after every update, to make sure all the configuration files are
compatible with updated software?
Given this is a server and the configs highly tweaked, I manually merge
them, but yes, I check regularly (and scan the pacman -Syu update for
notes about any manual changes needed) I don't use pacdiff as it is
impossible to read with the colors on traditional Linux color back
background in konsole/xterm.
I also have LTS on this server, so I booted the LTS kernel and it failed
in the exact same way. Network interface down, dhcpd4 failed to start.
(all other services are running, iptables, ipset, fail2ban, named,
avahi, apache/PHP, postfix, dovecot, sshd, samba, nut, mariadb,
postgresql, mongodb, etc..)
In dmesg output, curiously, the network device is brought up, but then
gets taken down again until I manually start it, e.g.
# dmesg | grep -i enp5
[ 23.138144] systemd[1]: Expecting device
/sys/subsystem/net/devices/enp5s0...
[ 26.867849] r8169 0000:05:00.0 enp5s0: renamed from eth0
[ 31.170658] r8169 0000:05:00.0 enp5s0: Link is Down
[ 33.382008] r8169 0000:05:00.0 enp5s0: Link is Up - 1Gbps/Full - flow
control rx/tx
[ 34.212934] r8169 0000:05:00.0 enp5s0: Link is Down
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[ 1409.078729] r8169 0000:05:00.0 enp5s0: Link is Down
[ 1411.306823] r8169 0000:05:00.0 enp5s0: Link is Up - 1Gbps/Full - flow
control rx/tx
The journal entries shows the interface coming up, and then being taken
down with no explanation for why it goes down, then it shows IPv6 coming
up as well when I manually bring the interface up a second time:
# journalctl -b --no-pager --full | grep enp5 | head -n50
Jun 28 02:17:05 valkyrie systemd[1]: Expecting device
/sys/subsystem/net/devices/enp5s0...
Jun 28 02:17:08 valkyrie kernel: r8169 0000:05:00.0 enp5s0: renamed from
eth0
Jun 28 02:17:12 valkyrie kernel: r8169 0000:05:00.0 enp5s0: Link is Down
Jun 28 02:17:15 valkyrie kernel: r8169 0000:05:00.0 enp5s0: Link is Up -
1Gbps/Full - flow control rx/tx
Jun 28 02:17:15 valkyrie avahi-daemon[711]: Joining mDNS multicast group
on interface enp5s0.IPv4 with address 192.168.6.14.
Jun 28 02:17:15 valkyrie avahi-daemon[711]: New relevant interface
enp5s0.IPv4 for mDNS.
Jun 28 02:17:15 valkyrie avahi-daemon[711]: Registering new address
record for 192.168.6.14 on enp5s0.IPv4.
Jun 28 02:17:15 valkyrie kernel: r8169 0000:05:00.0 enp5s0: Link is Down
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Jun 28 02:17:15 valkyrie avahi-daemon[711]: Interface enp5s0.IPv4 no
longer relevant for mDNS.
Jun 28 02:17:15 valkyrie avahi-daemon[711]: Leaving mDNS multicast group
on interface enp5s0.IPv4 with address 192.168.6.14.
Jun 28 02:17:15 valkyrie avahi-daemon[711]: Withdrawing address record
for 192.168.6.14 on enp5s0.
Jun 28 02:17:18 valkyrie named[801]: listening on IPv4 interface enp5s0,
192.168.6.14#53
Jun 28 02:40:10 valkyrie avahi-daemon[711]: Joining mDNS multicast group
on interface enp5s0.IPv4 with address 192.168.6.14.
Jun 28 02:40:10 valkyrie avahi-daemon[711]: New relevant interface
enp5s0.IPv4 for mDNS.
Jun 28 02:40:10 valkyrie avahi-daemon[711]: Registering new address
record for 192.168.6.14 on enp5s0.IPv4.
Jun 28 02:40:10 valkyrie kernel: r8169 0000:05:00.0 enp5s0: Link is Down
Jun 28 02:40:13 valkyrie kernel: r8169 0000:05:00.0 enp5s0: Link is Up -
1Gbps/Full - flow control rx/tx
Jun 28 02:40:14 valkyrie avahi-daemon[711]: Joining mDNS multicast group
on interface enp5s0.IPv6 with address fe80::feaa:14ff:fe9e:3319.
Jun 28 02:40:14 valkyrie avahi-daemon[711]: New relevant interface
enp5s0.IPv6 for mDNS.
Jun 28 02:40:14 valkyrie avahi-daemon[711]: Registering new address
record for fe80::feaa:14ff:fe9e:3319 on enp5s0.*.
Jun 28 02:41:43 valkyrie dhcpd[1781]: Listening on
LPF/enp5s0/fc:aa:14:9e:33:19/192.168.6.0/24
Jun 28 02:41:43 valkyrie dhcpd[1781]: Sending on
LPF/enp5s0/fc:aa:14:9e:33:19/192.168.6.0/24
Jun 28 02:41:47 valkyrie dhcpd[1781]: DHCPDISCOVER from
1c:93:c4:5b:30:87 (amazon-90e3375b8) via enp5s0
Jun 28 02:41:47 valkyrie dhcpd[1781]: DHCPOFFER on 192.168.6.113 to
1c:93:c4:5b:30:87 (amazon-90e3375b8) via enp5s0
Jun 28 02:41:47 valkyrie dhcpd[1781]: DHCPREQUEST for 192.168.6.113
(192.168.6.14) from 1c:93:c4:5b:30:87 (amazon-90e3375b8) via enp5s0
Jun 28 02:41:47 valkyrie dhcpd[1781]: DHCPACK on 192.168.6.113 to
1c:93:c4:5b:30:87 (amazon-90e3375b8) via enp5s0
Jun 28 02:41:58 valkyrie dhcpd[1781]: DHCPREQUEST for 192.168.6.114 from
b8:27:eb:67:78:cc (rp3bz) via enp5s0
<snip>
This has never happened before. Let me know what else you want to see
and I'll get it. Why is my enp5s0 device being brought up and then being
taken down?
Here are the relevant configs:
/etc/dhcpd.conf
option domain-name "mydomain.tld";
option routers gw.mydomain.tld;
option ntp-servers ns1.mydomain.tld;
option netbios-name-servers ns1.mydomain.tld;
option domain-name-servers 192.168.6.14, 192.168.6.17;
default-lease-time 3600;
max-lease-time 28800;
ddns-update-style interim;
ddns-updates on;
ignore client-updates;
include "/etc/named.keys";
include "/etc/dhcp_updater.key";
authoritative;
subnet 192.168.6.0 netmask 255.255.255.0 {
option domain-name "mydomain.tld";
ddns-domainname "mydomain.tld";
option subnet-mask 255.255.255.0;
option broadcast-address 192.168.6.255;
range dynamic-bootp 192.168.6.110 192.168.6.224;
default-lease-time 7200;
max-lease-time 28800;
zone mydomain.tld. {primary 127.0.0.1; key dhcp_updater; }
zone 6.168.192.in-addr.arpa. { primary 127.0.0.1; key
dhcp_updater; }
host wizard.mydomain.tld {
hardware ethernet 24:77:03:21:56:3c;
fixed-address 192.168.6.104;
}
host wiz.mydomain.tld {
hardware ethernet e4:11:5b:25:bf:d0; #eth0
fixed-address 192.168.6.105;
}
host picow1.mydomain.tld {
hardware ethernet fe:ed:de:ad:ba:be;
fixed-address 192.168.6.106;
}
}
/etc/systemd/system/netctl@ethernet\\x2dstatis\\x2dvalkyrie.service.d/profile.conf
[Unit]
Description=A basic static ethernet connection
BindsTo=sys-subsystem-net-devices-enp5s0.device
After=sys-subsystem-net-devices-enp5s0.device
There is nothing in /etc/systemd/network on any of my arch boxes.
The network config in /etc/netctl/ethernet-static-valkyrie (unchanged
since Nov 6 2022) is:
Description='A basic static ethernet connection'
Interface=enp5s0
Connection=ethernet
IP=static
Address=('192.168.6.14/24')
Gateway='192.168.6.11'
DNS=('192.168.6.14')
## For IPv6 autoconfiguration
#IP6=stateless
## For IPv6 static address configuration
#IP6=static
#Address6=('1234:5678:9abc:def::1/64' '1234:3456::123/96')
#Routes6=('abcd::1234')
#Gateway6='1234:0:123::abcd'
Any ideas?
--
David C. Rankin, J.D.,P.E.
