doc: update VRF support description

Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>

diff --git a/doc/user/Useful_Sysctl_Settings.md b/doc/user/Useful_Sysctl_Settings.md
index eaf97b969cc78e5430773284093d0313db557c12..0ebf9119b265b31536b303425a631089402ff13d 100644 (file)
--- a/doc/user/Useful_Sysctl_Settings.md
+++ b/doc/user/Useful_Sysctl_Settings.md
@@ -56,7 +56,4 @@ net.ipv6.neigh.default.base_reachable_time_ms=14400000
 
 # Use neigh information on selection of nexthop for multipath hops
 net.ipv4.fib_multipath_use_neigh=1
-
-# Allows Apps to Work with VRF
-net.ipv4.tcp_l3mdev_accept=1
 ```

diff --git a/doc/user/installation.rst b/doc/user/installation.rst
index dbd95aca403e960365f44ef7a5a639e5de09fa83..f7e45a62317ff67be584dc18d685733a973a9182 100644 (file)
--- a/doc/user/installation.rst
+++ b/doc/user/installation.rst
@@ -541,20 +541,15 @@ Additional kernel modules are also needed to support MPLS forwarding.
 
 :makevar:`VRF forwarding`
    General information on Linux VRF support can be found in
-   https://www.kernel.org/doc/Documentation/networking/vrf.txt. Kernel
-   support for VRFs was introduced in 4.3 and improved upon through
-   4.13, which is the version most used in FRR testing (as of June
-   2018).  Additional background on using Linux VRFs and kernel specific
-   features can be found in
-   http://schd.ws/hosted_files/ossna2017/fe/vrf-tutorial-oss.pdf.
-
-   A separate BGP TCP socket is opened per VRF.
-
-   **Important note** as of June 2018, Kernel versions 4.14-4.18 have a
-   known bug where VRF-specific TCP sockets are not properly handled. When
-   running these kernel versions, if unable to establish any VRF BGP
-   adjacencies, downgrade to 4.13. The issue was fixed in 4.14.57, 4.17.9
-   and more recent kernel versions.
+   https://www.kernel.org/doc/Documentation/networking/vrf.txt.
+
+   Kernel support for VRFs was introduced in 4.3, but there are known issues
+   in versions up to 4.15 (for IPv4) and 5.0 (for IPv6). The FRR CI system
+   doesn't perform VRF tests on older kernel versions, and VRFs may not work
+   on them. If you experience issues with VRF support, you should upgrade your
+   kernel version.
+
+   .. seealso:: :ref:`zebra-vrf`
 
 Building
 ^^^^^^^^

diff --git a/doc/user/zebra.rst b/doc/user/zebra.rst
index 0ad4f79d545b860ca051510334e784da076ed1e3..763170c973bf229a27f860616c3420cc733e00f0 100644 (file)
--- a/doc/user/zebra.rst
+++ b/doc/user/zebra.rst
@@ -261,8 +261,6 @@ Link Parameters Commands
    Allows nexthop tracking to resolve via the default route. This is useful
    when e.g. you want to allow BGP to peer across the default route.
 
-.. _zebra-vrf:
-
 Administrative Distance
 =======================
 
@@ -338,6 +336,8 @@ work FRR must use the same metric when issuing the replace command.
 Currently FRR only supports Route Replace semantics using the Linux
 Kernel.
 
+.. _zebra-vrf:
+
 Virtual Routing and Forwarding
 ==============================