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How to send multicast packets through a special interface in Linux

Having tried all possible methods, I could not find a job for this problem. I have a machine with two interfaces eth0 and eth2. I want all ff38: 40: 2001: dead: beef: cafe :: / 96 packages to continue eth2. I tried all of the following, but when I do ping6 ff38: 40: 2001: dead: beef: cafe :: 1 packages always go eth0. That I tried and did not work (i.e. the package still goes to eth0).

$> route add --inet6 ff38:40:2001:dead:beef:cafe::/96 gw 2003::100 dev eth2
$> route add --inet6 ff38:40:2001:dead:beef:cafe::/96 dev eth2
$> route add --inet6 ff38:40:2001:dead:beef:cafe::/96 metric 1 gw 2003::100 dev eth2

My routing table

[root@dev ~]# route --inet6  |grep eth0
fe80::/64                                   *                                       U     256    0        0 eth0
ff00::/8                                    *                                       U     256    0        0 eth0

[root@dev ~]# route --inet6  |grep eth2
2003::/64                                   *                                       U     256    68       0 eth2
fe80::/64                                   *                                       U     256    0        0 eth2
ff38:40:2001:dead:beef:cafe::/96            2003::100                               UG    1      0        0 eth2
*/0                                         fe80::c671:feff:fe14:e482               UGDA  1024   0        0 eth2
ff00::/8                                    *                                       U     256    0        0 eth2

However, ping6 ff38: 40: 2001: dead: beef: cafe :: 1 -I eth2 works just fine. Moreover, I see this problem only on Linux machines (MAC is ok).

[root@dev ~]# ping6 ff38:40:2001:dead:beef:cafe::1 -I eth2
PING ff38:40:2001:dead:beef:cafe::1(ff38:40:2001:dead:beef:cafe:0:1) from cal eth2: 56 data bytes
64 bytes from 2012::1: icmp_seq=0 ttl=253 time=19.1 ms
64 bytes from 2012::1: icmp_seq=1 ttl=253 time=2.16 ms
64 bytes from 2012::1: icmp_seq=2 ttl=253 time=2.14 ms
64 bytes from 2012::1: icmp_seq=3 ttl=253 time=2.26 ms
64 bytes from 2012::1: icmp_seq=4 ttl=253 time=2.08 ms
64 bytes from 2012::1: icmp_seq=5 ttl=253 time=2.15 ms

root@dev ~]# uname -a
Linux 2.6.18-194.el5 #1 SMP Tue Mar 16 21:52:39 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux

Perhaps the problem is that for eth0 there is ff00 :: / 8. How do I cancel this route. I also cannot delete the route ff00 :: / 8.

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1

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Linux:

$ ip -6 route show table local
local ::1 via :: dev lo  proto none  metric 0 
local fe80::213:a9ff:fe91:5bcb via :: dev lo  proto none  metric 0 
local fe80::250:b6ff:fe44:37d1 via :: dev lo  proto none  metric 0 
ff00::/8 dev eth0  metric 256 
ff00::/8 dev eth1  metric 256

$ ip -6 route show table main
fe80::/64 dev eth0  proto kernel  metric 256 
fe80::/64 dev eth1  proto kernel  metric 256 
ff15::/16 dev eth1  metric 1024
ff00::/8 dev eth1  metric 1024 

$ ip -6 rule show
0:      from all lookup local 
32766:  from all lookup main

... ff15:: 1 (5 == site-local, > link-local) eth0, "" "" , "" . , ff00::/8 .

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# ip -6 route add ff15::/16 dev eth1 table local

ff15:: 1 eth1.

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