6

After I upgraded Debian 9 to 10 Buster server lost network connection after 24 hours since reboot, I think problem is it can't renew IP address from DHCP server.

In /var/lib/dhcp I see the file dhclient.eth0.leases with expired date inside.

This service was ok with Debian 9, with Debian 10 I see this error:

root@debian:~# systemctl status networking.service
● networking.service - Raise network interfaces
   Loaded: loaded (/lib/systemd/system/networking.service; enabled;
vendor preset: enabled)
   Active: failed (Result: exit-code) since Thu 2019-07-25 15:18:02
CEST; 2h 39min ago
     Docs: man:interfaces(5)
  Process: 380 ExecStart=/sbin/ifup -a --read-environment
(code=exited, status=1/FAILURE)
 Main PID: 380 (code=exited, status=1/FAILURE)

Jul 25 15:18:01 debian-2gb-nbg1-2 dhclient[402]: DHCPREQUEST for
116.203.xx.xx on eth0 to 255.255.255.255 port 67
Jul 25 15:18:01 debian-2gb-nbg1-2 dhclient[402]: DHCPACK of
116.203.xx.xx from 172.31.1.1
Jul 25 15:18:01 debian-2gb-nbg1-2 ifup[380]: DHCPACK of 116.203.xx.xx
from 172.31.1.1
Jul 25 15:18:01 debian-2gb-nbg1-2 dhclient[402]: bound to
116.203.xx.xx -- renewal in 34516 seconds.
Jul 25 15:18:01 debian-2gb-nbg1-2 ifup[380]: bound to 116.203.xx.xx
-- renewal in 34516 seconds.
Jul 25 15:18:02 debian-2gb-nbg1-2 ifup[380]: RTNETLINK answers:
Permission denied
Jul 25 15:18:02 debian-2gb-nbg1-2 ifup[380]: ifup: failed to bring up eth0:0
Jul 25 15:18:02 debian-2gb-nbg1-2 systemd[1]: networking.service: Main
process exited, code=exited, status=1/FAILURE
Jul 25 15:18:02 debian-2gb-nbg1-2 systemd[1]: networking.service:
Failed with result 'exit-code'.
Jul 25 15:18:02 debian-2gb-nbg1-2 systemd[1]: Failed to start Raise
network interfaces.

Thanks for any help.

Edit: problem solved, looks like Debian 10 doesn't like disabling of IPv6 by the same way as v9 do.

If anyone knows how to disable IPv6 in Buster, let us know.

# disabling of IPv6 in Debian 9, not working in Debian 10
/etc/sysctl.conf
    net.ipv6.conf.all.disable_ipv6=1
    net.ipv6.conf.default.disable_ipv6=1
    net.ipv6.conf.lo.disable_ipv6=1
Roman_G
  • 63

1 Answers1

0

General debugging advice, set in /etc/default/networking

VERBOSE=yes

check all network configs

find /etc/network -type f -exec sh -c 'echo "$0" && cat $0' {} \;

In your case the problem is in /etc/network/interfaces.d/50-cloud-init.cfg where the attempt to configure static IPv6 will fail. Remove the file or comment IPv6 out:

inet6 static     address 2a01:4f8:c2c:xxxx::1/64

restart the service:

systemctl restart networking

and check logs:

journalctl -eu networking
Tombart
  • 2,523