doc: slirp supports ICMP echo if enabled in Linux
PATCH 1/1 doc: slirp supports ICMP echo if enabled in Linux
Since QEMU 0.15, slirp (user mode networking) supports ping to the Internet, see e6d43cfb1f9
Signed-off-by Gernot Hillier <[email protected]>
--- qemu-doc.texi | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)
qemu-doc.texi +11 -3
@@ -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 When using the built-in TFTP server, the router is also the TFTP server.
Signature · 1 line
1.8.4
Quoted 3 lines · Gernot Hillier
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