[PATCH v3] save exact route to remote target

[Marc Milgram]

Hi,

Sorry for the late response.

On 08/21/2014 08:34 AM, Baoquan He wrote:
> On 08/20/14 at 10:42am, Vivek Goyal wrote:
>
>> Hi Bao,
>>
>> Using "ip route get to" requires knowing the target. But that's little
>> different than bringing up an interface. There can be multiple static
>> routes going through an interface which lead to multiple targets.
>>
>> I think this makes the whole mechanism less generic. I liked the previous
>> method better where if we bring an interface, all the static routes going
>> through that interface will come up too. (Instead of only one static
>> route coming up for the target).
>>
>> So I would rather stick to the mechanism of determining all the routes
>> going through an interface and add the ones which are not present in
>> second kernel's routing table.
>
> I think you are right about this. Since Marc said other modules could
> use network too, such as heartbeat. In kdump we need build the network
> conf for it. I don't remember this clearly, need wait for Marc to check
> this.
>
> The reason I tried the exact route is some duplicate routes may exist in
> dracut. From dracut's point of view, it can handle route correctly if
> user can pass it the correct route. If duplicate routes are added,
> either we tolerate the warning message, or we require to change the
> implementation of dracut handling. But from dracut's side, they don't do
> anything wrong, why they need be changed.

I have found the following things that could each use a different route, 
and should be fully supported:
   * ssh/NFS/iscsi - but only one of these per configuration (as far as 
I know).
   * Name resolution (/etc/resolv.conf specifies this)
   * Heartbeat

I am not sure if we support:
   NIS (YP)

Additionally, customers could access the network through their own 
scripts, but it would be reasonable to not set up networks specifically 
for this.

Regards,

Marc