Media Bridge setup AC68U

[dl9pf]

I use 2 AC68 - one as AP, the 2nd as media-bridge.

After some time, some hosts on the media-bridge side of the network will not be able to ping the AP nor other internet hosts.
The situation can only be resolved for some time by rebooting the AP.

Is the number of hosts for a media bridge limited somehow ?!?!

E.g. :

[cable modem] <--> RT-AC68U as AP , IP .1 <--> RT-AC68U in bridge mode , IP .2 <---> some PCs .3/.5

While .3 has still access to the internet .5 looses it now and then.

 

[pete y testing]

whats the distance between the main router and the media bridge ? have you reserved the >2 address in the main router exclusively for the media bridge

in general with any type of bridge if the main router signal is ether interrupted or dropped for any reason the bridge will struggle to reconnect , so making sure the media bridge has adequate signal is important , what band are you connecting the bridge to ? 2.4 gig or 5 gig and what speed is the media bridge reporting as connecting at ?

 

[dl9pf]

Signal strengh is fine as the 2nd machine behind the bridge still has connectivity ... e.g.:

[cable modem] <--> RT-AC68U as AP , IP .1 <--> RT-AC68U in bridge mode , IP .2 <---> PCs .3/ and PC .5

While .3 still has connectivity to the internet and can ping the AP (.1), the PC with .5 after some time cannot reach the internet and the AP.
The PC with.3 is totally unaffected when this happens and can use the internet.
Can this be either a bridge (aging) or arp resolution issue ?

What I can tell is that the AP actually knows about the mac address of the failing host (.5). So I assume the forward routing works, just not the answer path maybe.

 

[sfx2000]

Sounds like an ARP issue at first glance... check the config on the 68U in bridge mode.

 

[sfx2000]

How are you connected between Router/AP 1 and the bridge? WiFi or ethernet?

 

[dl9pf]

Wifi 5GHz only

 

[dl9pf]

@sfx2000: I assume it is some arp issue or limitation wrt the number of hosts on the media-bridge side. how can I check that ? watching arp -a ?

 

[sfx2000]

@sfx2000: I assume it is some arp issue or limitation wrt the number of hosts on the media-bridge side. how can I check that ? watching arp -a ?

yes, solve that one first...

 

[dl9pf]

This is still the case even with firmware 380.59 . No idea how to resolve this.

 

[sparky3387]

I had the exact same issue, after my client pc went to sleep (after a few hours) the Asus rt-ac68u will no longer forward arp reply packets to the client (it will not do this if the PC sleeps for only a few minutes), I experienced the same issue if using the stock firmware, but surprisingly find no one else with the same issue. I fixed the issue by reverting to John's 374.43 V19E3. I tried many things and nothing, I could get arping packets from other clients (not connected directly to media brige) to the client, but not the other way.

 

[RMerlin]

Did you try adding static ARP entries? Not ideal if you have a lot of devices, but that might work.

Media Bridge is a Broadcom blackbox, so outside of our control.

 

[sparky3387]

Yeah I did, no response from the client. it would work fine from the bridge itself though. I tried many things (ifconfig down and up), forcing the bridge to ip_forward (even though its default is off) , I even went through all of proc/sys/net/ipv4 before and after to see if anything changed but could not see anything.....