[BL training-materials-updates] NFS booting: mention the "nfsvers=3" option

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git
On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=d429e48f00bda3571e0cd09b727e2a91188eb9af

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commit d429e48f00bda3571e0cd09b727e2a91188eb9af
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Thu Oct 4 13:39:52 2018 +0200

    NFS booting: mention the "nfsvers=3" option
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


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d429e48f00bda3571e0cd09b727e2a91188eb9af
 .../sysdev-root-filesystem-principles.tex                              | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/slides/sysdev-root-filesystem-principles/sysdev-root-filesystem-principles.tex b/slides/sysdev-root-filesystem-principles/sysdev-root-filesystem-principles.tex
index a6c8ac7..0baaddd 100644
--- a/slides/sysdev-root-filesystem-principles/sysdev-root-filesystem-principles.tex
+++ b/slides/sysdev-root-filesystem-principles/sysdev-root-filesystem-principles.tex
@@ -196,6 +196,9 @@ Kernel panic - not syncing: VFS: Unable to mount root fs on unknown block(0,0)
     \item \code{root=/dev/nfs} (we want rootfs over NFS)
     \item \code{ip=192.168.1.111} (target IP address)
     \item \code{nfsroot=192.168.1.110:/home/tux/rootfs/} (NFS server details)
+    \item You may need to add "\code{,nfsvers=3}" to the \code{nfsroot} setting,
+          as an NFS version 2 client may be rejected by the NFS server
+	  in recent GNU/Linux distributions.
     \end{itemize}
   \end{itemize}
 \end{frame}