Re: [libvirt] [PATCH] loopback is not always just lo

On 11/07/2016 04:15 AM, Daniel P. Berrange wrote: > On Mon, Nov 07, 2016 at 01:52:05AM -0500, Laine Stump wrote: >> On 11/06/2016 01:54 AM, Roman Bogorodskiy wrote: >>> Daniel P. Berrange wrote: >>> >>>> On Tue, Nov 01, 2016 at 06:15:59PM +0300, Pavel Timofeev wrote: >>>>> On BSD family OSes (Free/Net/Open/DragonFlyBSD, Mac OS) and >>>>> Solaris loopback interface is called 'lo0' instead of just 'lo'. >>>>> >>>>> --- >>>>> src/network/bridge_driver.c | 5 +++++ >>>>> 1 file changed, 5 insertions(+) >>>>> >>>>> diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c >>>>> index a3ee3f3..9d94d65 100644 >>>>> --- a/src/network/bridge_driver.c >>>>> +++ b/src/network/bridge_driver.c >>>>> @@ -1002,7 +1002,12 @@ networkDnsmasqConfContents(virNetworkObjPtr network, >>>>> virBufferAsprintf(&configbuf, "pid-file=%s\n", pidfile); >>>>> /* dnsmasq will *always* listen on localhost unless told otherwise */ >>>>> +#ifdef __linux__ >>>>> virBufferAddLit(&configbuf, "except-interface=lo\n"); >>>>> +#else >>>>> + /* BSD family OSes and Solaris call loopback interface as lo0 */ >>>>> + virBufferAddLit(&configbuf, "except-interface=lo0\n"); >>>>> +#endif >>>>> if (dnsmasqCapsGet(caps, DNSMASQ_CAPS_BIND_DYNAMIC)) { >>>>> /* using --bind-dynamic with only --interface (no >>>> ACK will push shortly. >>> This breaks all the networkxml2conftest tests, for example: >>> >>> $ VIR_TEST_DEBUG=1 VIR_TEST_RANGE=1 ./tests/networkxml2conftest >>> TEST: networkxml2conftest >>> 1) Network XML-2-Conf isolated-network ... >>> In '/home/novel/code/libvirt/tests/networkxml2confdata/isolated-network.conf': >>> Offset 303 >>> Expect [ >>> ] >>> Actual [0 >>> ] >>> $ >> On IRC the other day Roman mentioned the idea of just replacing "lo" with >> "lo*" on all platforms. I checked the dnsmasq documentation and this simple >> wildcarding is supported for the except-interface option, so I tried out >> such a patch on my system and it seems to work properly. Maybe we should do >> that instead of having yet another chunk of #ifdef __linux__ code (the test >> case datafiles will still need to be changed, but at least they'll be >> identical for all platforms). > Any idea how far back wildcards work. If they still work on the RHEL-6 > vintage dnsmasq, then I'd agree with you and it'll make the test case > fix easier to avoid the conditional. Time for the "Monday Sigh". Sigh. I looked this up in dnsmasq's git repo, and it seems recognition of wildcards in interface names was added in commit 49333cbdbef3bf86198b31a42bffad002de305d5 Author: Simon Kelley <simon(a)thekelleys.org.uk&gt; Date: Fri Mar 15 20:30:51 2013 +0000 Allow trailing '*' wildcard in interface names. That commit was first in dnsmasq 2.66, but RHEL6 is using dnsmasq 2.48. The strange thing is that I tried running dnsmasq on RHEL6 with "--except-interface=lo*" and was able to run multiple instances. I guess my test was flawed. (NetworkManager doesn't support use of dnsmasq for DNS services, as Cole suggested as a test in: https://bugzilla.redhat.com/show_bug.cgi?id=886663#c2 But the source doesn't lie.) So I guess we need to parameterize the tests somehow (this seems familiar, but I can't remember why).