check_dhcp

[Glen Barber]

On Thu, Jul 24, 2014 at 09:25:06PM -0600, Warren Block wrote:
> On Thu, 24 Jul 2014, Glen Barber wrote:
> 
> >On Thu, Jul 24, 2014 at 09:14:24PM -0600, Warren Block wrote:
> >>net-mgmt/monitoring-plugins has a check_dhcp program used to test the
> >>availability of a remote DHCP server.  It has BSD-specific code, but seems
> >>fairly dated and only works when all supposedly optional parameters are
> >>given.  However, it does work on a normal machine:
> >>
> >>  OK: Received 1 DHCPOFFER(s), 1 of 1 requested servers responded, max lease time = 600 sec.
> >>
> >>But it does not work inside a jail, seeing no offers:
> >>
> >>  CRITICAL: No DHCPOFFERs were received.
> >>
> >>Raw sockets and bpf are enabled in the jail.  dhclient in the jail can
> >>actually get a lease.  Is there anything else that needs to be configured to
> >>allow this to work in a jail?
> >>
> >>
> >>
> >>After 'make -C /usr/ports/net-mgmt/monitoring-plugins', the code in question
> >>is check_dhcp.c in
> >>work/monitoring-plugins-monitoring-plugins-b5611ea/plugins-root.  It gives
> >>these type of errors:
> >>
> >>  % ./check_dhcp -s 192.168.1.1
> >>  Error: if_nametoindex error - Device not configured.
> >>
> >>  % ./check_dhcp -s 192.168.1.1 -i em0
> >>  Error: Couldn't get hardware address from em0. sysctl 2 error - No such file or directory.
> >>
> >>After adding -m <jail card's MAC>, it gives no errors but never sees a
> >>response.
> >
> >The problem, I suspect, is that bpf(4) does not exist in the jail.
> 
> It's there:
> 
> # ls -lh /dev/b*
> crw-------  1 root  wheel   0x12 Jul 24 21:00 /dev/bpf
> lrwxr-xr-x  1 root  wheel     3B Jul 24 20:08 /dev/bpf0 -> bpf
> 

This is within the jail?

> dhclient would not work without it, I think.  But something else is
> different between the jail and a real machine.

Glen

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-jail/attachments/20140724/95d962a7/attachment.sig>