On 04/27/16 12:26, Thomas Huth wrote: > On 27.04.2016 12:05, Laszlo Ersek wrote: >> On 04/26/16 22:12, Thomas Huth wrote: >>> On 26.04.2016 21:25, Programmingkid wrote: >>>> On Apr 26, 2016, at 3:00 PM, Dr. David Alan Gilbert wrote: >> >>>>> Does ping work? >>>> I can ping the virtual router at 10.0.2.2. Any other ip address fails. >>> >>> That's normal for user-mode / slirp networking. You can't ping external >>> hosts with this mode. >> >> Side note: yes, you can. >> >> I do it whenever I want to check network connectivity from within ad-hoc >> OVMF guests, using the PING command of the UEFI shell. ("Ad-hoc guest" >> implies user-mode / slirp.) >> >> It can be enabled with the following steps: >> >> (1) Determine the main group ID (or one supplementary group ID) of the >> user that will run QEMU with slirp. >> >> (2) In /etc/sysctl.conf (or whatever is appropriate for your host >> distro), make sure that the whitespace separated inclusive group ID >> range in the "net.ipv4.ping_group_range" sysctl includes the above group ID. > > Wow, thanks for that hint, I just tried by temporarily enabling it with > > sudo sysctl net.ipv4.ping_group_range=... > > and indeed it works! > > Maybe we should document that somewhere? > For example http://qemu-project.org/Documentation/Networking currently > only says: "ICMP traffic does not work (so you cannot use ping within a > guest)" ...
Done. Laszlo