[pve-devel] [PATCH pve-common] fix #4299: network : disable_ipv6: fix path checking

[R. Grieger]

Hello everyone,
at first let me tell you sorry, if I incorrectly adhere to the mailing lists format. I did not subscribe prior to this email, but I try to reference the most helpful mails in this body.

I initially reported the issue in the proxmox-forums here:https://forum.proxmox.com/threads/vxlan-error-512-disable_ipv6.116691/  How did I hit this isue? I started off using the proxmox with ipv4 only and wanted to progress to ipv6, when I have the time to.

Until i fully go ipv6, the proxmox host, a reverse proxy and firewall run ipv6 and further hosts are provided ipv6 traffic via the proxy. The ipv4 deactivation is usually no issue, only when using SDN with VXLAN.
Whenever I upgrade proxmox now, the script get rolled back and every system with an attached VXLAN breaks at reboot.

Is there any chance this patch will be applied at all? Otherwise I will just build a bash-script workaround to apply this patch to my instance.

> I'm really unable to reproduce this.
>
>
> User is able to reproduce it 100%, depending on the brigde where the vm is started.
>
> (some bridge with sdn generated for example).
> 
> I don't have asked to user to reboot.
>
>
>
> ifupdown2 seem to thrown warning too, so I don't known if it's a special sysctl triggering this, or a kernel bug, or something else.
>
>________________________________
> From: Wolfgang Bumiller <w.bumiller at proxmox.com  <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>>
> Sent: Thursday, October 20, 2022 12:05 PM
> To: Alexandre Derumier <aderumier at odiso.com  <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>>
> Cc: pve-devel at lists.proxmox.com  <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>  <pve-devel at lists.proxmox.com  <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>>
> Subject: Re: [pve-devel] [PATCH pve-common] fix #4299: network : disable_ipv6: fix path checking
>
> On Thu, Oct 20, 2022 at 12:24:29AM +0200, Alexandre Derumier wrote:
>>/It's possible to have a />>//proc/sys/net/ipv6/ directory />>//>>/but no />>//proc/sys/net/ipv6/conf/$iface/disable_ipv6 />
> Do we know why this happens? That doesn't seem right to me, unless
> some kind of race somewhere with the interface creation?
> Or is there a legitimate kernel option that causes this?
>
>>//>>/Signed-off-by: Alexandre Derumier <aderumier at odiso.com 
<https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>> />>/--- />>/src/PVE/Network.pm | 2 +- />>/1 file changed, 1 insertion(+), 1 deletion(-) />>//>>/diff --git a/src/PVE/Network.pm b/src/PVE/Network.pm />>/index c468e40..9d726cd 100644 />>/--- a/src/PVE/Network.pm />>/+++ b/src/PVE/Network.pm />>/@@ -210,8 +210,8 @@ my $cond_create_bridge = sub { />>//>>/sub disable_ipv6 { />>/my ($iface) = @_; />>/- return if !-d '/proc/sys/net/ipv6'; # ipv6 might be completely disabled />>/my $file = "/proc/sys/net/ipv6/conf/$iface/disable_ipv6"; />>/+ return if !-e $file; # ipv6 might be completely disabled />>/open(my $fh, '>', $file) or die "failed to open $file for writing: $!\n"; />>/print {$fh} "1\n" or die "failed to disable link-local ipv6 for $iface\n"; />>/close($fh); />>/-- />>/2.30.2/