forcing IGMPv2

[d.a.glynos]

On Mon, 29 May 2006, Anthony Petropoulos wrote:
> Geia sas,
>
> Gnwrizei kaneis an/pws ginetai mia efarmogh na steilei IGMPv2 request
> (kai oxi IGMPv3) gia na kanei join ena multicast group, enw o pyrhnas
> einai IGMPv3 enabled? Kapoio option sto socket isws?
>
> Eyxarhstw.

Rixnontas mia grhgorh matia sto source:
/usr/src/linux/net/ipv4/igmp.c
kai sto doc:
http://www-static.cc.gatech.edu/~gantsich/IGMPv3/IGMPv3-TR.pdf

h ru8mish de ginetai per-efarmogh alla per-interface. Gia na valei o admin
thn eth0 se v2 mode:

echo "2" > /proc/sys/net/ipv4/conf/eth0/force_igmp_version

To default mode e3artatai apo ton upstream router, o opoios an uposthrizei
v2 (kai sunepws stelnei tetoia queries stous hosts) 8etei ton purhna tou
host se v2 compatibility mode (des to igmp_timer_expire() sta sources).
Se periptwsh pou o router den exei dei3ei shmadia v1 h' v2 tote paizeis
se v3.

H kyria diafora meta3u v2 kai v3 einai ta source filters.

An esy de xrhsimopoihseis source filters kai apla arkesteis sto
IP_{ADD/DROP}_MEMBERSHIP tote to application sou paragei paketa pou einai
compatible me oles tis ekdoseis (v1, v2, v3).

hope this clarifies things.
dimitris