[Qemu-devel] [PATCH] add text about how to use qemu-nbd with qemu

[xiawenc@linux.vnet.ibm.com]

From: Wenchao Xia <xiawenc@linux.vnet.ibm.com>

  Qemu system emulator reports only fails that make people confused
about why, when it is invoked with nbd block device tring to connect
qemu-nbd server. In fact qemu will try connect server for several
times but server only accept one connect by default.
  I paid some times to find out why it fails. This patch add special
text to explain how to use it in such case.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
---
 qemu-nbd.texi |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/qemu-nbd.texi b/qemu-nbd.texi
index 6955d90..014040a 100644
--- a/qemu-nbd.texi
+++ b/qemu-nbd.texi
@@ -44,6 +44,12 @@ Export QEMU disk image using NBD protocol.
   display this help and exit
 @item -V, --version
   output version information and exit
+
+  Note: When qemu-nbd was used to export a disk that would be used by QEMU
+block device, -t or --persistent must be set for that QEMU nbd client would try
+connect more than one time. For eg:
+  qemu-nbd ./simple.img -p 10809 -t
+  qemu -hdb nbd:127.0.0.1:10809
 @end table
 
 @c man end
-- 
1.7.1