Disable IPv4, Enable IPv6

[FragKing]

Hi guys

Seems like i'm missing something here.


System:

- Fedora 10
- NO X-Server, cmdline only
- 1 NIC

My expectations:

- Disable IPv4 (yes, v4!) (or just not retrieve a v4 IP)
- Enable IPv6, and get an IP via DHCP6C, including DNS information

Behaviour:

- IPv6 does work, but only stateless configuration (using Router Advertisement, it constructs an IP Address from the announced Prefix), and it does not get it from DHCP6, DNS information is missing, too (/etc/resolv.conf)
- I can Ping outside Hosts (e.g. ipv6.google.com)
- I get a DHCP IPv4

My config:

/etc/sysconfig/network:

NETWORKING=yes
HOSTNAME=<hostname>
NETWORKING_IPV6=yes

/etc/sysconfig/networking/devices/ifcfg-eth0:

# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]
DEVICE=eth0
HWADDR=00:50:56:bf:7a:ae
ONBOOT=yes
SEARCH="<local domain>"
BOOTPROTO=dhcp
USERCTL=no
NETWORKING_IPV6=yes
IPV6INIT=yes
DHCPV6C=yes
NM_CONTROLLED=yes
TYPE=Ethernet
PERSISTENT_DHCLIENT=yes
DHCLIENTARGS="-nw"

For IPv4 disabling:

I have tried setting BOOTPROTO to "none", "static", as well as NETWORKING=no
I can't get it to work that there is NO IPv4 address assigned via DHCP.
I always receive an IP, no matter what I do.


For IPv6 enabling:

If I manually run the dhcp6c client (dhcp6c -f eth0), I get assigned an IPv6 IP to eth0, and /etc/resolv.conf is updated successfully.

I just can't it to work that it does it automatically.
I'm sure I'm missing a simple thing here....

Thanks & Cheers
Michel

[FragKing]

OK guys.

I figured that it's probably a little complicated.

Enabling IPv6 with DHCP:
The problem seems to be the NetworkManager.

Disabling NetworkManager (chkconfig NetworkManager disable) and enabling the "standard" Networking (chkconfig network enable) did the trick.

As for disabling IPv4 on the same interface, it gets tricky.
It seems possible if you have set a static IPv4 address, but the script does not respect having NO IPv4 address.

I ended up editing /etc/sysconfig/networking-scripts/ifup-eth:

added the following after line 225 (/etc/sysconfig/network-scripts/ifup-ipv6 ${CONFIG}):

if [[ "${DHCPV6C}" = [Yy1]* ]] && [ -x /sbin/dhcp6c ]; then
/sbin/dhcp6c ${DEVICE};
dhcp6_pid=(`/bin/ps -eo 'pid,args' | /bin/grep "dhcp6c ${DEVICE}" | egrep -v grep`);
echo ${dhcp6_pid[0]} > /var/run/dhcp6c_${DEVICE}.pid
fi

This initializes IPv6 dhcp if required, even if the IPv4 interface is NOT dhcp, and has NO ip address.

Cheers
Michel