Here what I mean.
Before enabling rp_filter:
net.ipv4.conf.all.rp_filter = 0 net.ipv4.conf.default.rp_filter = 0 net.ipv4.conf.eth0.rp_filter = 0 net.ipv4.conf.eth1.rp_filter = 0 net.ipv4.conf.eth2.rp_filter = 0 net.ipv4.conf.l2tpeth1.rp_filter = 0 net.ipv4.conf.lo.rp_filter = 0
After enabling:
net.ipv4.conf.all.rp_filter = 2 net.ipv4.conf.default.rp_filter = 2 net.ipv4.conf.eth0.rp_filter = 2 net.ipv4.conf.eth1.rp_filter = 2 net.ipv4.conf.eth2.rp_filter = 2 net.ipv4.conf.l2tpeth1.rp_filter = 2 net.ipv4.conf.lo.rp_filter = 2
After disabling:
net.ipv4.conf.all.rp_filter = 0 net.ipv4.conf.default.rp_filter = 2 net.ipv4.conf.eth0.rp_filter = 2 net.ipv4.conf.eth1.rp_filter = 2 net.ipv4.conf.eth2.rp_filter = 2 net.ipv4.conf.l2tpeth1.rp_filter = 2 net.ipv4.conf.lo.rp_filter = 2