diff mbox

doc: slirp supports ICMP echo if enabled in Linux

Message ID 53BE9CB5.4060503@siemens.com
State New
Headers show

Commit Message

Gernot Hillier July 10, 2014, 2:01 p.m. UTC 
Since QEMU 0.15, slirp (user mode networking) supports ping to the
Internet, see e6d43cfb1f9

Signed-off-by: Gernot Hillier <gernot.hillier@siemens.com>
---
  qemu-doc.texi | 14 +++++++++++---
  1 file changed, 11 insertions(+), 3 deletions(-)


  When using the built-in TFTP server, the router is also the TFTP
  server.

Comments

Michael Tokarev July 18, 2014, 5:40 a.m. UTC | #1 
10.07.2014 18:01, Gernot Hillier wrote:
> 
> Since QEMU 0.15, slirp (user mode networking) supports ping to the
> Internet, see e6d43cfb1f9

Applied to the trivial tree, after removing an extra empty line and
rewording the last part to be "To allow ping for GID 100 (usually
users group)", because not all linux systems may use this GID for
users group.  Thank you!

/mjt
diff mbox

Patch

diff --git a/qemu-doc.texi b/qemu-doc.texi
index 551619a..fc6e57d 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -1205,9 +1205,17 @@  In order to check that the user mode network is 
working, you can ping
  the address 10.0.2.2 and verify that you got an address in the range
  10.0.2.x from the QEMU virtual DHCP server.

-Note that @code{ping} is not supported reliably to the internet as it
-would require root privileges. It means you can only ping the local
-router (10.0.2.2).
+Note that ICMP traffic in general does not work with user mode networking.
+@code{ping}, aka. ICMP echo, to the local router (10.0.2.2) shall work,
+however. If you're using QEMU on Linux >= 3.0, it can use unprivileged ICMP
+ping sockets to allow @code{ping} to the Internet. The host admin has 
to set
+the ping_group_range in order to grant access to those sockets. To 
allow ping
+for the users group (GID 100):
+
+@example
+
+echo 100 100 > /proc/sys/net/ipv4/ping_group_range
+@end example