IPv6 not working in Azure Linux VM

RSLmatrix 6 Reputation points
2020-04-29T13:59:18.79+00:00

I have a Centos 7 VM deployed in Azure. I am attempting to make it reachable on the Internet via a public IPv6 address but so far it is failing. I cannot ping any IPv6 host from the VM, nor can the host be reached from the internet. The IPv4 functionality is working fine.

I've already performed the following actions:

Added IPv6 subnet to the Virtual Network address space.
Created a new NIC with dynamic IPv4 and IPv6 addresses.
Attached public addresses to the NIC.
Attached the NIC to the VM.
Removed the old NIC.

The public and private IP addresses all appear on the VM overview screen.

I don't know if there is a problem with the VM configuration itself or if there are wider issues with the Azure environment. I've pasted in output from various commands in case they are useful. Any help appreciated, thank you!

/etc/sysconfig/network-scripts/ifcfg-eth0:

DEVICE=eth0
ONBOOT=yes
BOOTPROTO=dhcp
TYPE=Ethernet
USERCTL=no
PEERDNS=yes
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_FAILURE_FATAL=no
NM_CONTROLLED=yes
PERSISTENT_DHCLIENT=yes

/sbin/ifconfig eth0:

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.0.0.4  netmask 255.255.255.0  broadcast 10.0.0.255
        inet6 fdd8:ea16:eddf:f7c6::4  prefixlen 128  scopeid 0x0<global>
        inet6 fe80::20d:3aff:feb5:9345  prefixlen 64  scopeid 0x20<link>
        ether 00:0d:3a:b5:93:45  txqueuelen 1000  (Ethernet)
        RX packets 42014275  bytes 39983428126 (37.2 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 28333743  bytes 39875144405 (37.1 GiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

ip -6 route show:

unreachable ::/96 dev lo metric 1024 error -113 pref medium
unreachable ::ffff:0.0.0.0/96 dev lo metric 1024 error -113 pref medium
unreachable 2002:a00::/24 dev lo metric 1024 error -113 pref medium
unreachable 2002:7f00::/24 dev lo metric 1024 error -113 pref medium
unreachable 2002:a9fe::/32 dev lo metric 1024 error -113 pref medium
unreachable 2002:ac10::/28 dev lo metric 1024 error -113 pref medium
unreachable 2002:c0a8::/32 dev lo metric 1024 error -113 pref medium
unreachable 2002:e000::/19 dev lo metric 1024 error -113 pref medium
unreachable 3ffe:ffff::/32 dev lo metric 1024 error -113 pref medium
fdd8:ea16:eddf:f7c6::4 dev eth0 proto kernel metric 100 pref medium
fdd8:ea16:eddf:f7c6::/64 dev eth0 proto ra metric 100 pref medium
fe80::/64 dev eth0 proto kernel metric 100 pref medium
default via fe80::1234:5678:9abc dev eth0 proto ra metric 100 pref medium
Azure Virtual Machines
Azure Virtual Machines
An Azure service that is used to provision Windows and Linux virtual machines.
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  1. Ronen Ariely 15,106 Reputation points
    2020-05-01T03:01:11.237+00:00

    Good day,

    Check the following step-by-step tutorial:

    https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-ipv4-ipv6-dual-stack-standard-load-balancer-powershell

    Seems like the solution is based on using load balancer, as explained here.

    1 person found this answer helpful.