Oracle IPv6 problem

[davidsarkany]

I installed Debian to my Oracle ARM VM and followed this guide.

ip a output:

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 02:00:17:00:aa:2b brd ff:ff:ff:ff:ff:ff
    altname enp0s3
    inet 10.0.0.191/24 brd 10.0.0.255 scope global dynamic eth0
       valid_lft 86388sec preferred_lft 86388sec
    inet6 fe80::17ff:fe00:aa2b/64 scope link 
       valid_lft forever preferred_lft forever

I found a workaround. I manually installed the dhclient and run the command from the terminal. dhclient -6 eth0

How can I solve this issue?

[bohanyang]

It's weird. My current network file is:

[Match]
Name = eth0

[Network]
DHCP = ipv4
NTP = 169.254.169.254

[DHCPv4]
UseHostname = false

It's working at least for me.

Maybe you don't have to use systemd-networkd, but just stick to to old ifup & /etc/interfaces

You can refer to https://github.com/bohanyang/debi/discussions/81

[bohanyang]

I manually installed the dhclient

Usually dhclient should be pre-installed and it's used by ifupdown & /etc/interfaces

In my guide, I purged it since systemd-networkd can do DHCP by itself.

[davidsarkany]

I did a clean Debian 12 install.

Create a new file /etc/systemd/network/10-eth0.network with the following content.

[Match]
Name = eth0

[Network]
DHCP = ipv4
NTP = 169.254.169.254

[DHCPv4]
UseHostname = false

Run this command: systemctl stop networking && systemctl stop ifup@eth0 && systemctl start systemd-networkd

then this:

systemctl enable systemd-networkd
apt purge -y --auto-remove ifupdown isc-dhcp-client

After the reboot I don't have IPv6 connection

[zijiren233]

seem,debian 12, kernel version: 6.1.0-9-amd64, use bbr fq_pie then i install isc-dhcp-client and use cmd: dhclient -6 eth0, i getted IPv6 connection

[davidsarkany]

I set IPv6 address directly, and works

[Match]
Name = eth0

[Network]
DHCP=ipv4
NTP = 169.254.169.254
Address=2603:XXXX:Y:XXXX:XXXX:YYY:XXXX:XXXX/64

[bohanyang]

All IPv6 in my Oracle VMs are down suddenly.

[davidsarkany]

All IPv6 in my Oracle VMs are down suddenly.

My config still works.

[bohanyang]

Yeah, so maybe there's an issue of Oracle's DHCP / IPv6 auto config.