[pve-devel] [PATCH docs 3/3] network: shortly document disabling ipv6 support

[Stoiko Ivanov <s.ivanov@proxmox.com>]

Given that quite a few HOWTOs on the internet suggest disabling ipv6
support via kernel commandline, which can cause quite many undesired
side-effects (e.g. ip6tables as used in pve-firewall errors out)
this patch adds a short section documenting, that disabling ipv6 is
not necessary usually and if needed better done via sysctl.

Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
---
 pve-network.adoc | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/pve-network.adoc b/pve-network.adoc
index add220e..37667b8 100644
--- a/pve-network.adoc
+++ b/pve-network.adoc
@@ -548,6 +548,25 @@ iface vmbr0 inet manual
 
 ----
 
+Disabling IPv6 on the Node
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+{pve} works correctly in all environments, irrespective of whether IPv6 is
+deployed or not. We recommend leaving all settings at the provided defaults.
+
+Should you still need to disable support for IPv6 on your node, do so by
+creating an appropriate `sysctl.conf (5)` snippet file and setting the proper
+https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt[sysctls],
+for example adding `/etc/sysctl.d/disable-ipv6.conf` with content:
+
+----
+net.ipv6.conf.all.disable_ipv6 = 1
+net.ipv6.conf.default.disable_ipv6 = 1
+----
+
+This method is preferred to disabling the loading of the IPv6 module on the
+https://www.kernel.org/doc/Documentation/networking/ipv6.rst[kernel commandline].
+
 ////
 TODO: explain IPv6 support?
 TODO: explain OVS
-- 
2.20.1