Date: Thu, 24 Jul 2014 21:25:06 -0600 (MDT) From: Warren Block <wblock@wonkity.com> To: Glen Barber <gjb@FreeBSD.org> Cc: freebsd-jail@FreeBSD.org Subject: Re: check_dhcp Message-ID: <alpine.BSF.2.11.1407242122540.3624@wonkity.com> In-Reply-To: <20140725032045.GY1065@hub.FreeBSD.org> References: <alpine.BSF.2.11.1407242042240.3624@wonkity.com> <20140725032045.GY1065@hub.FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
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 dhclient would not work without it, I think. But something else is different between the jail and a real machine.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?alpine.BSF.2.11.1407242122540.3624>