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Issue Problem adding second IPv6 address

hansitheking

Basic Pleskian
Hello,

I have a IPv6/64 subnet for my Server. The first IPv6 address XYZ1:XYZ1:XYZ1:XYZ1:: is running very well. If I am adding a second address Plesk will add a new line (up /sbin/ifconfig ens3 inet6 add XYZ1:XYZ1:XYZ1:XYZ1::1/64) to the /etc/network/interfaces and it will look like this:

Code:
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto ens3
iface ens3 inet dhcp

# ipv6
iface ens3 inet6 static
    up /sbin/ifconfig ens3 inet6 add XYZ1:XYZ1:XYZ1:XYZ1::1/64
   address XYZ1:XYZ1:XYZ1:XYZ1::
   netmask 64
   gateway fe50::1

The IPv6 address is working, but once the server is rebooted the second IPv6 address is no more working. I have to run
Code:
sudo /sbin/ifconfig ens3 inet6 add XYZ1:XYZ1:XYZ1:XYZ1::1/64
or
Code:
sudo ip addr add XYZ1:XYZ1:XYZ1:XYZ1::1/64 dev ens3
or
use the repair function in the Plesk Panel before the second IPv6 address is working.

If I am using the repair function in the Plesk Panel, Plesk will add a second line to the /etc/network/interfaces stating (up /sbin/ifconfig ens3 inet6 add XYZ1:XYZ1:XYZ1:XYZ1::1/64).

I allready tested adding the IP address manual in the /etc/network/interfaces and afterwards in Plesk but the behaviour is the same.
 
I've had exactly the same issue for uncountable times. Last time tow days ago I also created the ip_map.txt file by a tutorial by my provider 1and1 according to PLESK and dedicated server.
In this file I wrote the second IPv6 and ran the script again. But after rebooting always the nginx conf of domain is broken and the IPv6 in IP pool is also broken (repair IP link is visible).
Everything is okay after repairing IPv6 in IP-Pool, and also the nginx conf can be recreated.
But after the next reboot everything is broken again, no matter if you use the IPv6 as dedicated or shared IP.
So, I don't try to use additional IPv6 any longer. Think it has be to do with global nginx configuration file. server.nginx.conf, whatever.
There exist also tutorials to integrate the IPv6 subnet, my subnet is XYZ:0/56, but I don't want to play with this additional IPv6 any longer.

Greets
 
Last edited:
I think I solved the Issue.

I added a file /etc/sysctl.d/ipv6.conf with the following content, therefore the IPv6-Route is no more expiring.
Code:
net.ipv6.conf.default.accept_ra=0
net.ipv6.conf.default.autoconf=0
net.ipv6.conf.all.accept_ra=0
net.ipv6.conf.all.autoconf=0
net.ipv6.conf.eth0.accept_ra=0
net.ipv6.conf.eth0.autoconf=0

Also I added these two firewall rules:
Code:
ip6tables -A INPUT -p icmpv6 -j ACCEPT
ip6tables -A OUTPUT -p icmpv6 -j ACCEPT
 
Please try the following change:

Code:
# sysctl config
net.ipv4.ip_forward=1
net.ipv4.conf.all.rp_filter=1
net.ipv4.icmp_echo_ignore_broadcasts=1
# ipv6 settings (no autoconfiguration)
net.ipv6.conf.default.autoconf=0
net.ipv6.conf.default.accept_dad=0
net.ipv6.conf.default.accept_ra=0
net.ipv6.conf.default.accept_ra_defrtr=0
net.ipv6.conf.default.accept_ra_rtr_pref=0
net.ipv6.conf.default.accept_ra_pinfo=0
net.ipv6.conf.default.accept_source_route=0
net.ipv6.conf.default.accept_redirects=0
net.ipv6.conf.all.autoconf=0
net.ipv6.conf.all.accept_dad=0
net.ipv6.conf.all.accept_ra=0
net.ipv6.conf.all.accept_ra_defrtr=0
net.ipv6.conf.all.accept_ra_rtr_pref=0
net.ipv6.conf.all.accept_ra_pinfo=0
net.ipv6.conf.all.accept_source_route=0
net.ipv6.conf.all.accept_redirects=0
net.ipv6.conf.all.forwarding=1

If interface created then:
net.ipv6.conf.INTERFACE.accept_dad=0
 
I have the same issue with an second ipv4 address. The address works but after server reboot I must use repair link. I don't know how can I solve this.

Gesendet von meinem Nexus 5X mit Tapatalk
 
I discovered a new tutorial by 1and1 support adding and changing IPv4 on dedicated server AND dynamic cloud server.
Yesterday I did it.
By this tut. it's also possible to change the main/default IPv4.
1. Debian/Ubuntu, 2. CentOS, 3. Suse 13x
Dedicated server (Easy understanding by shell screens also for english users):
IPv4-Adresse auf Dedicated Server Linux ändern oder hinzufügen - 1&1 Hilfe Center
Dynamic Cloud server (link looks the same, but is different in path):
IPv4-Adresse auf Dedicated Server Linux ändern oder hinzufügen - 1&1 Hilfe Center

But for the main problem that it is not possible adding IPv6 on Ubuntu with 1and1 and Plesk there is no real solution.

Greets
 
Last edited:
My servers are located at Hetzner. Maybe you can do something with the configuration though.

I basically turn Proxmox before my server. The sysctl config must be inserted under Proxmox to the ipv6 address is forwarded and in each KVM host.

Proxmox network config
Code:
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet manual
      
auto vmbr0
iface vmbr0 inet static
  address  XX.XX.XX.XX
  netmask  255.255.255.XXX
  gateway  XX.XX.XX.XX
  bridge_ports eth0
  bridge_stp off
  bridge_fd 0
  up ip route add XX.XX.XX.XX/32 dev vmbr0 #Only this line for other IPv4 addresses

iface vmbr0 inet6 static
  address  XXXX:XXX:XXX:XXXX::2 #Use a static ipv6 not: XXXX:XXX:XXX:XXXX::
  netmask  64
  gateway  fe80::1

KVM Host network config
Code:
auto lo
iface lo inet loopback

auto ens18
iface ens18 inet static
  address XX.XX.XX.XX #Other IPv4 Address
  netmask 255.255.255.255
  gateway XX.XX.XX.XX

iface ens18 inet6 static
  address  XXXX:XXX:XXX:XXXX::100 #new ipv6 address for plesk
  netmask  64
  gateway  XXXX:XXX:XXX:XXXX::2 #gateway ipv6 from "iface vmbr0 inet6 static"

Now you can add more IPv6 Addresses in plesk. Do not forget to implement the sysctl config. Otherwise there may be problems with a restart.
 
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