kern/106722: [net] [patch] ifconfig may not connect an interface to known network

[Anton Yuzhaninov]

Wednesday, March 14, 2007, 7:00:13 PM, Bruce M. Simpson wrote:

BMS> Gleb Smirnoff wrote:
>> AFAIK, the problem needs a more generic approach. I see two approaches.
>>
>> 1) Introduce RTM_CHANGEADD, a command that will forcibly add route,
>> deleting all conflicting ones. Use this command in in_addprefix().
>>
>> 2) In rt_flags field we still have several extra bits. We can use
>> them to specify route source - RTS_CONNECTED, RTS_STATIC, RTS_XXX,
>> where XXX is a routing protocol. When issuing RTM_ADD a route with
>> a preferred source (e.g. CONNECTED vs STATIC) will override the old
>> one.
>>

BMS> I understand that they are being proposed to address problems we 
BMS> currently have in the stack, i.e. that we do not support multipathing,
BMS> though it is more than likely they will be blown away in future when the
BMS> architecture changes (and it has to change).

IMHO question is not related to multipathing.
Kernel routes now don't contain administrative distance and it root of
this problem.

RTS_CONNECTED, RTS_STATIC is a hack adding some fixed AD values
without increasing route size in memory.

-- 
 WBR,
 Anton Yuzhaninov