[libvirt] [PATCH v3] leaseshelper: improvements to support all events

[Nehal J Wani]

On Wed, Aug 20, 2014 at 4:23 PM, Roman Bogorodskiy
<bogorodskiy at gmail.com> wrote:
>   Nehal J Wani wrote:
>
>> This patch enables the helper program to detect event(s) triggered when there
>> is a change in lease length or expiry and client-id. This transfers complete
>> control of leases database to libvirt and obsoletes use of the lease database
>> file (<network-name>.leases). That file will not be created, read, or written.
>> This is achieved by adding the option --leasefile-ro to dnsmasq and passing a
>> custom env var to leaseshelper, which helps us map events related to leases
>> with their corresponding network bridges, no matter what the event be.
>>
>> Also, this requires the addition of a new non-lease entry in our custom lease
>> database: "server-duid". It is required to identify a DHCPv6 server.
>>
>> Now that dnsmasq doesn't maintain its own leases database, it relies on our
>> helper program to tell it about previous leases and server duid. Thus, this
>> patch makes our leases program honor an extra action: "init", in which it sends
>> the known info in a particular format to dnsmasq by printing it to stdout.
>>
>> ---
>>
>>  This is compatible with libvirt 1.2.6 as only additions have been
>>  introduced, and the old leases file (*.status) will still be supported.
>>
>>  v3: * Add server-duid as an entry in the lease object for every ipv6 lease.
>>      * Remove unnecessary variables and double copies.
>>      * Take value from DNSMASQ_OLD_HOSTNAME if hostname is not known.
>>
>>  v2: http://www.redhat.com/archives/libvir-list/2014-July/msg01109.html
>>
>>  v1: https://www.redhat.com/archives/libvir-list/2014-July/msg00568.html
>>
>
> JFI: I did a basic testing and it's working fine for me so far.
>
>> diff --git a/src/network/leaseshelper.c b/src/network/leaseshelper.c
>> index c8543a2..e984cbb 100644
>> --- a/src/network/leaseshelper.c
>> +++ b/src/network/leaseshelper.c
>
>
>> @@ -176,6 +188,10 @@ main(int argc, char **argv)
>>      if (argc == 5)
>>          hostname = argv[4];
>>
>> +    /* In case hostname is still unkown, use the last known one */
>
> s/unkown/unknown/
>
>> +    if (!hostname)
>> +        hostname = virGetEnvAllowSUID("DNSMASQ_OLD_HOSTNAME");
>> +
>
> Roman Bogorodskiy

Ping!

-- 
Nehal J Wani