[libvirt] [PATCH-v4 2/2] Support for static routes on a virtual bridge

[Gene Czarcinski]

On 04/25/2013 03:13 PM, Gene Czarcinski wrote:
> On 04/22/2013 11:59 AM, Laine Stump wrote:
>> address should be optional unless prefix or netmask is non-0, although
>> I've now noticed that won't be handled properly due to
>> virSocketAddrGetIpPrefix returning -1 when there is no address or prefix
>> or netmask (I'm fixing that before I push that patch, so you can just
>> toss your 1/2 patch, rebase, and assume it's fixed).
> I have most of the stuff reworked except for the address, gateway, 
> netmask, and prefix code.  Getting all of those balanced so they work 
> correctly is a bit tricky..
>
> 1.  For <route>, I am requiring that both address= and gateway= be 
> specified with address='0.0.0.0' and address='::' being valid 
> addresses.  For IPv4, netmask='0.0.0.0' works correctly but prefix=0 
> does not.
>
> For IPv4, address='0.0.0.0' results in a default route.  I am not sure 
> what all these extra default routes are going to do to things but lets 
> not get in the way of the experimenter.
>
> For IPv6, this address='::', prefix='0' is a slightly different matter 
> as default routes are usually handled differently.  I am going to go 
> ahead and implement it but I am not sure it is a good idea.  
> "Normally," if you do not specify a prefix for IPv6, the default is 
> 64.  But if you do specify one, then it will be used.
>
> It is getting real close and it should be ready "real soon now" ;))
>
AARRRRGH!!!!

With IPv4 using address='0.0.0.0' and netmask='0.0.0.0' things work just 
fine but with prefix not so much.  The problem is that with prefix=0, it 
is not in the xml which then results it it defaulting at a later time.  
This is an extreme corner case.  Usually a zero prefix is just ignored.

Gene