[qpimd-users] Re: [quagga-users 11073] querry related with is there any MRT in pim

[Everton Marques]

Hi Bhavin,

I think the Linux MFC is a data-plane, kernel-side, representation of the MRT.

I don't think there is a size limit for the MFC, but I am only guessing, since
I haven't studied its code. You can check the MFC code here:
http://lxr.linux.no/linux+v2.6.30.6/net/ipv4/ipmr.c

pimd does not have an explicit MRT table, but every global
S,G entry is hold as an "struct pim_upstream", and the list
of all global S,G entries is kept under "qpim_upstream_list".
By "global" (S,G) I mean it is not an interface-specific state.

Everton

On Tue, Sep 8, 2009 at 9:43 PM, <address@hidden> wrote:
> Hello Everton,
>    Wha i mean is that pimd directly enteres the S,G entries in to
> the MFC. I think there must be a limit on the no. of S,G entries which
> can be accomodate in to MFC. MRT tends for multicastr routing table which
> is maintained by router to forward multicast traffic. Is it mainly because
> pimd deals with SSM so it does not have MRT? (MRT: for e.g. pimd can
> have S,G Multicast routing table where it will have table containing
> all S,G entries).
>
> Regards,
> Bhavin
>
>> Hi Bhavin,
>>
>> You mistakenly addressed address@hidden,
>> please use address@hidden instead.
>>
>> On Sat, Sep 5, 2009 at 10:48 AM, <address@hidden> wrote:
>>>
>>>    This time i have done some reading before sending any mail.
>>> I have gone through the code of pim_mroute in pim daemon and it
>>> shows that S,G entry is added to the MFC but what if it exceeds
>>> it limits then is there any MRT or as such provision?
>>
>> Which limit are you worried about?
>>
>> One limit I am aware of is the number of interfaces in the
>> output interface list (OIL). You probably noticed that limit
>> is MAXVIFS as defined in <linux/mroute.h>. pimd
>> tracks the number of vif_index in use with the global
>> counter "qpim_mroute_oif_highest_vif_index".
>>
>> I don't know what MRT stands for, please clarify...
>>
>> Cheers,
>> Everton
>>
>
>