[staticanime]

That's correct.

If you don't want to - and this also works at quite a few other hosting companies that are not yet IPv6 ready - you can use a 6to4 tunnel as well.

There are several ways to do this, for example, you can use "192.88.99.1" gateway to use the nearest IPv4->IPv6 tunnel provider. All you need to do is calculate you IPv6 equivalent of your IPv4 address, which you can do with this command:

printf "2002:%02x%02x:%02x%02x::1\n" $(echo 91.12.34.56 | tr . ' ')

Where "91.12.34.56" is obviously the actual IP address. In the above example, you would get a result like this:

2002:5b0c:2238::1

That would be the IPv6 address for your server to use, like in the following example for Ubuntu/Debian's /etc/network/interfaces:

auto tun6to4
iface tun6to4 inet6 v4tunnel
    address 2002:5b0c:2238::1
    netmask 16
    gateway ::192.88.99.1
    endpoint any
    local 91.12.34.56

(keep note of the gateway [always 192.88.99.1] and the endpoint [your server's IP address])

An alternative, which is a bit overkill if you already have an IPv6 block from OVH (which excludes OVH's cloud servers), you could use Hurricane Electric's tunnel broker service. See http://tunnelbroker.net for more details on that.

Ah, ok, cool, the 6 to 4 tunnel is perfect for my needs, thanks for explaining guys

[Myatu]

So, wait, I can use the IPv6 block my server has for any VM's, alongside my IPv4 failovers, therefore, doing more or less the same job as the failover alias's, but for IPv6.

That's correct.

If you don't want to - and this also works at quite a few other hosting companies that are not yet IPv6 ready - you can use a 6to4 tunnel as well.

There are several ways to do this, for example, you can use "192.88.99.1" gateway to use the nearest IPv4->IPv6 tunnel provider. All you need to do is calculate you IPv6 equivalent of your IPv4 address, which you can do with this command:

printf "2002:%02x%02x:%02x%02x::1\n" $(echo 91.12.34.56 | tr . ' ')

Where "91.12.34.56" is obviously the actual IP address. In the above example, you would get a result like this:

2002:5b0c:2238::1

That would be the IPv6 address for your server to use, like in the following example for Ubuntu/Debian's /etc/network/interfaces:

auto tun6to4
iface tun6to4 inet6 v4tunnel
    address 2002:5b0c:2238::1
    netmask 16
    gateway ::192.88.99.1
    endpoint any
    local 91.12.34.56

(keep note of the gateway [always 192.88.99.1] and the endpoint [your server's IP address])

An alternative, which is a bit overkill if you already have an IPv6 block from OVH (which excludes OVH's cloud servers), you could use Hurricane Electric's tunnel broker service. See http://tunnelbroker.net for more details on that.

[staticanime]

So, wait, I can use the IPv6 block my server has for any VM's, alongside my IPv4 failovers, therefore, doing more or less the same job as the failover alias's, but for IPv6. I thought I'd need seperate IPv6 address ranges for each IPv4 address I had?

[Razakel]

Is there a way to calculate/find the IPv6 equivelant of an OVH IPv4 fail-over IP?

You don't get v6 versions of failovers. You get a /64 for the server, which is listed on the overview page of the manager.

I'd really like to know what you're doing that requires more than 18,446,744,073,709,551,616 v6 addresses.

[staticanime]

Is there a way to calculate/find the IPv6 equivelant of an OVH IPv4 fail-over IP?

[Zoom]

Does that work on the new OVH kernel on lenny and squeeze?

[Myatu]

use sysctl to disable it.

"net.ipv6.conf.all.disable_ipv6 = 1" in your /etc/sysctl.conf to be specific...

[yonatan]

Anyone have a way to DISABLE IPV6 from OVH kernels? Some of my programs that use java has problems with ipv6.

use sysctl to disable it.

[Zoom]

Anyone have a way to DISABLE IPV6 from OVH kernels? Some of my programs that use java has problems with ipv6.

[RapidSeeds]

thanks myatu,
much <3 to you for all of this information

[Myatu]

Glad it works. There's no risks to keeping this in Netboot mode - might actually make life a bit easier, as any security updates to the kernel applied by OVH simply requires a reboot on your end and you're good to go. Your only downside is that the kernel is not modular (but the one from the hd wasn't either) - in many cases it's not an issue though.

[RapidSeeds]

it works,

but can i stay in this mode? are their risks if I do?
or should i boot from HD again?

[makno]

check again if you got ipv6 support and if the answer is yes than assign an ipv6 to the machine and you should be good to go

[RapidSeeds]

hey myatu,

i've switched to ipv6 kernel and netboot.
now i've done hard reboot.

what should i do now?

[Myatu]

It's very simple actually. Go to your OVH Manager, pick the dedicated server, then select "Services".

You should see a "Netboot" icon (also used for things like Rescue Mode, etc) - select that and simply choose from the available kernels, taking care of choosing one that has "ipv6" in its name for obvious reasons

Click the "Accept" button and after a minute or so reboot your server (you should do a hard reboot, also from the "Services" menu for your dedicated server in the manager).

Should you run into any issues with the netboot kernel, you can easily revert it to what you currently have by selecting "hd" from the Netboot options, then restarting the server again.

[RapidSeeds]

lsmod | grep ipv6
Opening /proc/modules: No such file or directory

this netboot thing sounds too complex for me :P wouldn't want to mess anything up
could you tell me exactly what to do? if it is too much for me, then i accept that

[Myatu]

It does seem odd that IPv6 wasn't included with the OVH distro, especially since they give you IPv6 IPs. So I'd try the modprobe first, and do one more double check with "lsmod | grep ipv6". Otherwise, give the netboot kernels a try (like the ones with GRC, etc. - there's one specifically with IPv6 enabled).

[RapidSeeds]

Yes, I used ovh manager.

I will have to reboot into netboot mode?

[Myatu]

Was the OS installed through OVH's manager? If so, you can change the kernel in the Netboot option (pick the one with IPv6 enabled). Otherwise, double check with a "modprobe ipv6"

[RapidSeeds]

You do NOT have IPv6 support

Why not? I thought all modern OSes were capable of ipv6

[Myatu]

how can i find out which kernel i have?
im using debian lenny clean install

Cut & paste:

test -f /proc/net/if_inet6 && echo "You have IPv6 support" || echo "You do NOT have IPv6 support"

and check the response

[RapidSeeds]

Give it a full reboot, just in case. And you are using an IPv6 ready kernel, right?

how can i find out which kernel i have?
im using debian lenny clean install

[Myatu]

Give it a full reboot, just in case. And you are using an IPv6 ready kernel, right?

[RapidSeeds]

"SIOCADDRT: File exists" = "SIOC": Serial Input Output Controller, "ADD": Add, "RT": Route, "File exists": Route already configured.

Fairly innocent and likely related to the IPv4 address (route wasn't cleared before/after the interface was pulled back up). An "ifconfig" should show your IPv6 address though.

ifconfig only shows ipv4 address:

eth0      Link encap:Ethernet
          inet addr:91.xxx.xxx.xxx  Bcast:91.xxx.xxx.xxx  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          collisions:0 txqueuelen:1000 
          Interrupt:27 Base address:0xc000

and still can't access ipv6 servers

[Myatu]

"SIOCADDRT: File exists" = "SIOC": Serial Input Output Controller, "ADD": Add, "RT": Route, "File exists": Route already configured.

Fairly innocent and likely related to the IPv4 address (route wasn't cleared before/after the interface was pulled back up). An "ifconfig" should show your IPv6 address though.

[RapidSeeds]

I added netmask 56
but:

# /etc/init.d/networking restart
Reconfiguring network interfaces...SIOCADDRT: File exists
Failed to bring up eth0.
done.

the file looks like this (below the regular ipv4 stuff):

iface eth0 inet6 static
address 2001:41D0:1:xxFF::1
netmask 56
gateway 2001:41D0:1:xxFF:FF:FF:FF:FF

any idea?

[Myatu]

iface eth0 inet6 static
        address 2001:41d0:1:xxxx::1
        netmask 56
        # optional, not required in most cases:
        gateway 2001:41d0:1:xxff:ff:ff:ff:ff

You do need the netmask for OVH though. They use LAN segments (/56) which are further delegated in a /64 block for you to use (hence the wonky gateway entry, which normally isn't needed for IPv6 as it's auto-configured otherwise).

[makno]

you don't need the netmask for ipv6

[RapidSeeds]

I use ubuntu, and just added a route in /etc/network/interfaces.

I needed to get some information from my OVH manager - IPV6 address - in my case

2001:41D0:1:588e::/64

You need to work out the gateway address from this which is easy enough to do - the first three parts are the same as your IPV6 address, the next one needs the last 2 characters changing to FF and then FF:FF:FF:FF adding, which in my case gives the following:
address 2001:41D0:1:588E::1
gateway 2001:41D0:1:58FF:FF:FF:FF:FF

Each server can have /56 addresses (72,057,594,037,927,935 possible addresses but unfortunately you have to assign them manually.

You don't need to use miredo, just configure your network card.

Try reading http://help.ovh.co.uk/Ipv4Ipv6 for OVH's information page.

Ok. So I should add it like this:
iface eth0 inet6 static
address [Address]
netmask [Prefix]
gateway [Router]

And what would the 'netmask' be?

[NickW]

Now what about the hexadecimal value of "0000"? Is that "nothing" or "0" or...? Well, this is where the IPv6 abbreviation come into play. Normally, it's "0". So the following IPv6 address 2001:41D0:0000:5803:0000:0000:0000:0001 can safely be rewritten as 2001:41D0:0:5803:0:0:0:1.

This can also be written as 2001:41D0:0000:5803::0001 or 2001:41D0:0:5803::1

[Myatu]

Each server can have /56 addresses (72,057,594,037,927,935 possible addresses but unfortunately you have to assign them manually.

The /56 is an extremely annoying subnet mask used by OVH (which breaks a lot of stuff that can't use LAN segments). In actuality you can "only" assign /64 addresses though (but /56 is still needed for the OVH configuration). Nevertheless, that's a whopping 18,446,744,073,709,551,616 possible IP addresses you can use

I still cant get my head around the numbers involved in IPv6!!

The thing that might confuse some regarding its notation is the permitted use of abbreviations and hexadecimal values.

For IPv4 it's 4 sets of numbers ranging from 0..255, the hexadecimal equivalent of 00h..FFh (a byte); in IPv6, it's 8 sets of numbers ranging from 0..65535, the equivalent of 0000h..FFFFh (unsigned word);

As for hexadecimal values, the leading zero is insignificant as long as we know the full range. So for IPv6, we could for example reduce "000F" to simply "F". "0D22" becomes "D22", etc. So an IPv6 address of 2001:41D0:0001:5803:0001:0002:0003:0004 can be shortened to 2001:41D0:1:5803:1:2:3:4.

Now what about the hexadecimal value of "0000"? Is that "nothing" or "0" or...? Well, this is where the IPv6 abbreviation come into play. Normally, it's "0". So the following IPv6 address 2001:41D0:0000:5803:0000:0000:0000:0001 can safely be rewritten as 2001:41D0:0:5803:0:0:0:1.

But the portion of 0:0:0 can further be reduced with the double-colon abbreviation (:. You can read it as "two or more sets of zeros", whereby we understand that sets are normally separated by a single colon. So the same IPv6 address above becomes 2001:41D0:0:5803::1. The remaining zero in this example can't be replaced by the double-colon for two reasons: 1) it's not two or more sets (just a single set) and 2) you can use the double-colon only once in an IPv6 address.

The 127.0.0.1 of IPv6 is 0000:0000:0000:0000:0000:0000:0001 and is simply rewritten as ::1. Most applications, which use "0.0.0.0" for a "Listen to all IPs" (ie., a web server) use the "[::]" or "::" for "Listen to all IPv6 addresses".

Now, since you have trillions of more IP addresses to pick from in IPv6, the subnets are different from IPv4 as well. For IPv4 you end at /32 (which is equivalent to a "255.255.255.255" subnet mask).

For IPv6 you end at /128. So using 2001:41D0:1:5803:1:2:3:4 again as an example:

2001:... = /16
2001:41D0:... = /32
2001:41D0:1:... = /48
2001:41D0:1:5803:... = /64
2001:41D0:1:5803:1:... = /80
2001:41D0:1:5803:1:2:... = /96
2001:41D0:1:5803:1:2:3... = /112
2001:41D0:1:5803:1:2:3:4 = /128

Interestingly, the smallest network subnet that can be assigned to an end user is /64. You'd think that's a bit of a waste of the world's available IPv6 addresses - especially since IPv4 has almost been used up by "wasting" - but if you look at it by the number of available IPs, it'll show something different...

Each /32 addressing gives 65536 subnets. Each of those have yet another 65536 subnets. 65536 x 65536 is 4,294,967,296 - the total amount of IPv4 addresses (including the private and reserved IP ranges). Then each of those 4 billion+ are further delegated by a /64 (18,446,744,073,709,551,616 IPs). So it's enough for each person in the world to give every dust particle in their house its own IP address without conflicts...

I hope this makes some sense!

[jonlewi5]

Each server can have /56 addresses (72,057,594,037,927,935 possible addresses but unfortunately you have to assign them manually.

I still cant get my head around the numbers involved in IPv6!!

[gregoryfenton]

I use ubuntu, and just added a route in /etc/network/interfaces.

I needed to get some information from my OVH manager - IPV6 address - in my case

2001:41D0:1:588e::/64

You need to work out the gateway address from this which is easy enough to do - the first three parts are the same as your IPV6 address, the next one needs the last 2 characters changing to FF and then FF:FF:FF:FF adding, which in my case gives the following:
address 2001:41D0:1:588E::1
gateway 2001:41D0:1:58FF:FF:FF:FF:FF

Each server can have /56 addresses (72,057,594,037,927,935 possible addresses but unfortunately you have to assign them manually.

You don't need to use miredo, just configure your network card.

Try reading http://help.ovh.co.uk/Ipv4Ipv6 for OVH's information page.

[RapidSeeds]

does anyone know how i can access ipv6 websites from my server?
do i have to install miredo or something like that?