IGMP on rt-ac86u with VLAN settings.

[Vegard Engen]

I recently bought an AC86U that I am pretty happy with. It currently runs 384.14_2.

I have managed to get the IGMP proxy with my IPTV working with standard VLAN settings, and also when I run WAN on a tagged network.

I also bought a switch, TP-LINK TL-SG108e, that I specifically bought for its VLAN capabilities. This, I have managed to get working.

On my switch, I have two VLANs, one that is my LAN behind the router, and one that is my WAN. My switch is located some meters away, and due to WAF reasons, I'd like to minimize the number of cables run. I would also like to save some ports, although that is not currently an issue.

I now have solved it by running the LAN segment (VLAN 4) on my switch with a non-tagged connection to one of the ethernet-ports, and a tagged Internet-connection (VLAN 2) on the WAN port. This setup works excellent with the internal IGMP proxy.

After extensive searching - there isn't all that much documentation, I found that the IGMP proxy is mcpd. This is configured through mcpd.conf, which is customizable in Asuswrt merlin. I have managed to get this working, and having it using my customized mcpd.conf.

But, here comes my problem: There is actually not all that much information out there what I can do in mcpd.conf.

When I run VLAN4 in through the VAN port, tagged, gets it into the LAN by adding a VLAN4 tagged interface on eth0, and bridge it to the internal br0, my Internet works perfectly still. But my IPTV, which is the multicast and IGMP stuff, completely fails.

Have anyone good overview of how mcpd is configured? Or have some good links to me? I have randomly tried adding vlan4 to configuration entries here and there, but it is so far fruitless guesswork.

Stock mcpd.conf:

##### IGMP configuration #####
igmp-default-version 3
igmp-query-interval 20
igmp-query-response-interval 100
igmp-last-member-query-interval 10
igmp-robustness-value 2
igmp-max-groups 25
igmp-max-sources 25
igmp-max-members 25
igmp-fast-leave 1
igmp-admission-required 0
igmp-admission-bridging-filter 0
igmp-proxy-interfaces vlan2
igmp-snooping-interfaces br0
igmp-mcast-interfaces vlan2

##### MCAST configuration #####
igmp-mcast-snoop-exceptions 239.255.255.250/255.255.255.255 224.0.255.135/255.255.255.255
mld-mcast-snoop-exceptions ff05::0001:0003/ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff

Would be grateful to any hints to how mcpd works. I am not too familiar with IGMP at all, really.

 

[XIII]

I found that the IGMP proxy is mcpd. This is configured through mcpd.conf, which is customizable in Asuswrt merlin.

How can one customise this?

Reason for asking: I'm trying to make SSDP work over OpenVPN. On the internet "smcroute" or "igmpproxy" are suggested. While I can install both using Entware they don't start, because something else is already running. By accident I discovered it is "mcpd"...

 

[Vegard Engen]

How can one customise this?

Reason for asking: I'm trying to make SSDP work over OpenVPN. On the internet "smcroute" or "igmpproxy" are suggested. While I can install both using Entware they don't start, because something else is already running. By accident I discovered it is "mcpd"...

See https://github.com/RMerl/asuswrt-merlin/wiki/Custom-config-files

Basically, you put the configuration file you want mcpd to use in /jffs/configs, and then mcpd will use that instead.

I found the running mcpd.conf as /var/mcpd.conf when I logged in to my router, so you can copy that to /jfss/configs to use as a starting point.

Still haven't solved my own problem, though

 

[XIII]

Did you find documentation for the mcpd config file?

(I killed "mcpd" and tried "smcroute" which did now start, but the suggested smcroute configuration line "mroute from tun21 group 239.255.255.250 to br0" did not solve my problem)

 

[Vegard Engen]

Did you find documentation for the mcpd config file?

(I killed "mcpd" and tried "smcroute" which did now start, but the suggested smcroute configuration line "mroute from tun21 group 239.255.255.250 to br0" did not solve my problem)

Unfortunately, I did not find any documentation for mcpd config file. I also know that there is supposedly some hardware limits that limits what IGMP snooping stuff the ac86 can do. It could be that this also prevents mcpd to do what I want