TTL is not increased with iptables command

Hi,

I try to get DLNA working fine over a VPN and have to increase TTL for some clients. I have installed iptables-mod-ipopt and iptables-mod-physdev. Followed both ways described here but bridged should be the right: https://www.maroonmed.com/ttl-modification-for-outgoing-traffic-with-openwrt/

TCPDUMP: 20:34:18.145815 IP (tos 0x0, ttl 3, id 32103, offset 0, flags [DF], proto UDP (17), length 158)
    192.168.175.165.49155 > 239.255.255.250.1900: UDP, length 130

My setup is br-lan bridged to tap_vpn (outgoing VPN connection). Every client using TTL 4 works fine and TTL 2 is dropped in the routing chain. Any ideas what is going wrong???

Cheers,
Nils

Yes, it is bridged, therefore it won't be hitting iptables and there is no point in increasing TTL in a bridged network since it doesn't decrease as it doesn't hop any router.

Solved. :slight_smile: Against the howto I have to restart the router and everything is fine. ... If somebody run into the same...do a restart. :wink:

But on my main net I have some hops so I have to increase it because of that. I like to increase hops at my client router and not central even if that would be possible too.

When we say hops, we mean router hops. Bridged interfaces don't count as router hops.

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