IPv6 support in XCP-ng for the management interface - feedback wanted

stormi

Reviving this thread. @BenjiReis worked hard to bring ipv6 support for the management interface of hosts, contributed many pull requests to the XAPI project for that, modified the installer and xsconsole to make them compatible with ipv6, created a test ISO image, but we got no feedback at all.

So I'm calling for help from the community again: there's no way we can get every real world situations in our lab, and you collectively have vastly superior knowledge about networking than we have alone, so if we want this feature to be more than an experiment in the next XCP-ng release, we need feedback from testers.

If you have the hardware and time to test, please consider jumping in

BenjiReis

a little recap of the thread for anyone who'd like to help us by testing the feature.

XCP-ng IPv6 recap

A test ISO is available to test a new feature: having your XCP-ng hosts with an IPv6 management interface.

To have an IPv6 host, you must either install a new host or upgrade one with the test ISO.

More info on the dedicated blogpost
Please give any feedback in this thread!

Known limitations

IPv6 Static only for now
HA not tested yet
Dual stack (both IPv4 and IPv6) can lead to DNS issues and the host will use IPv4 for its XAPI operations.

AtaxyaNetwork

Hello all !

I was able to make some tests these last days on my lab servers.
My lab is currently 1 Dell R610 with IPv6 only. I plan to add 2 more servers to test all the features.

I already noticed some blocking points:

The DNS server (v6) that I gave at installation is no longer present once the server is installed. I had to edit /etc/resolv.conf and add my server by hand to have working DNS.
Once the server is installed, I tried to do a quick deploy via https://xen-orchestra.com/?#!/xoa, without success. I asked @olivierlambert to add a AAAA DNS record, because it was not there in the first place, but once the record was added, the quick deploy still didn't work. I don't have any debug message to give back, and I don't know how to debug more

Feel free to contact me if you want to do some live testing, or if you need more information !

Thanks for all this work !

Cécile ~ AtaxyaNetwork

olivierlambert

Thanks a lot for your feedback

@BenjiReis will come back to you soon!

BenjiReis

@ataxyanetwork hi! Thanks for the feedback.

Did you set your host in both ipv4 & ipv6?

AtaxyaNetwork

@benjireis Hello !

For now, I set only IPv6 in my lab.

I wanted to test the different features in an IPv6 environment only.

I can add IPv4, but I think the aim is to have XCP-ng working in IPv6, right ?

Cécile ~ AtaxyaNetwork

BenjiReis

@ataxyanetwork you're right. I just wanted to know to reproduce as much as possible your environment. Plus IPv6 only will be easier to debug, dual mode can have some weird magic happening at time!

I'll take a look ASAP and post here about my findings

AtaxyaNetwork

@benjireis Great !

Don't hesitate to ping me if you have questions !

Cécile ~ AtaxyaNetwork

LeMatz

Hey guys,

first thing we found during the installation:

The DNS dialogue doesn't like the shortest possible way to write an IPv6. According to my local nslookup, the IP notation is correct.

But if I fill the zeroes out, everything works fine:

Thanks,
Matthias

LeMatz

Hey guys,

one more thing:

On the console, we are able to see the network address:

But on XCP-ng Center, the IP is not shown:

I'm not sure, if this is merely a problem with the Center, or if XOA has this problem as well. We are not able to install the XOA, as we tried to bind our free IPv4 address to XOA as well and just got an error:

Cheers,
Matthias

olivierlambert

Thanks for your feedback @LeMatz

@BenjiReis will take a look.

For the short notation, I think that was simply not taken into account.
What about the repo? It should work out of the box (our repo are IPv6 compatible)
XCP-ng Center is not maintained by us, so we won't solve this anyway. For XO, it should work out of the box. Your issue is with the XO deploy thing, we are aware of it

LeMatz

Hey @olivierlambert,

sure thing, thanks.

I edited the thing with the repo out of my post, I was just a bit too blind.

Is there any way on the XCP-ng host to test the DNS resolution? "dig" is not available there. Our host is somehow not able to resolve to mirrors.xcp-ng.org.
Our chosen DNS server is very well able to resolve your mirror.

I know that XCP-ng Center is not maintained by your team, but it's currently the only GUI that works for us :).

Is there a different way to deploy XO instead of the quick install? I'm not sure, if the build from source is worth the effort.

Thanks again,
Matthias

hoerup

@lematz
In the first picture of "hostname and dns configuration":
It doesn't look like you have any double colon '::' in the first 2 entries but you have them in all fields on the last picture

LeMatz

@hoerup Jeeez, you are right, thanks a lot.
I'm feeling bad now

Reminder: do not work past 9 p.m. :D.

olivierlambert

haha good catch, so it might support short format ipv6 Can you double check?

LeMatz

@olivierlambert Well, I'd like to. But the console is giving me a hard time.

Our given DNS servers were not recognized:

I'm not able to change the entries. Hitting "Enter" does not do anything. For all the other entries works "Enter" perfectly.

Olivier recommended in https://xcp-ng.org/forum/topic/5412/installation-of-xo-with-just-one-ip/2?_=1642003322780 to use one IPv6 for dom0 and bind the IPv4 to a VM like pfSense. Thanks to MAC-address binding of our provider, that made everything worse. Of cause we can't have the same MAC-address on more than one NIC.

I think this IPv6 experiment ends here for us.

Thanks for all the answers and help!
Matz

olivierlambert

Sadly @BenjiReis is really busy ATM working on our next 8.2.1 release But he'll come back here as soon he can!

LeMatz

It's okay, releases are important

Dennis 0

Short format works fine

IPv6-only server still running for almost a year now without problems.

Not using it for anything mission critical as of yet, as installing updates is a bit "exciting" trying to combine main repo with the experimental ipv6-repo (avoid overwriting ipv6-patched packages on update) but still getting CVE's fixed from kernel etc. Haven't broken anything yet (AFAIK) - just looking forward to see this in a release.

(+ There might be a few useful details hiding here: https://github.com/xcp-ng/xcp/issues/437 in case)

DennisGlindhart created this issue in xcp-ng/xcp

closed IPv6 support on host #437

BenjiReis

Hi all! Long time no see ^^

I'm glad to say i'm back on IPv6 and will (soon-ish) provide a new IPv6 iso to test XCP-ng with an IPv6 management interface.
I've made some fixes to DNS management.

Before the new ISO i'd like to support ideally DHCPv6 and autoconf.
For now I managed to :

sometimes have an IP with DHCPv6 and sometimes a DNS - no gateway but it's exepected with stateless DHCPv6.
Have an IP with Autoconf - No Gateway & no DNS

I'm looking for help as my field of expertise is more ocaml dev than IPv6.
I'm thinking especially of @AtaxyaNetwork and @bnerickson that I know have more knowledge than me for IPv6. Any help from a forum users would be greatly appreciated.

For DHCPv6 this is the conf of dhclient:

interface "xenbr0" {
  send fqdn.fqdn = gethostname();
  request subnet-mask, broadcast-address, time-offset, host-name, interface-mtu, dhcp6.nis-servers, dhcp6.nisp-servers, nis-domain-name, nisp-domain-name, dhcp6.sntp-servers, dhcp6.fqdn, routers, dhcp6.domain-search, dhcp6.name-servers;
}

For Autoconf here's what's done:

/sbin/sysctl -q -w net.ipv6.conf.xenbr0.autoconf=1
/sbin/sysctl -q -w net.ipv6.conf.xenbr0.accept_ra=1

Am I missing something obvious? I can provide more info if requested.
Also I can made available a test iso before the real one but it'd be really a experimental ISO.

Thanks!