Bonjour not working in Wifi/Ethernet

el.pescado said:

Hi,

I have a MacBook Pro with Mountain Lion installed, a Linux PC that serves as file server (using Netatalk), and a D-Link DIR-300 router. When all devices are connected via Ethernet, everything works fine.

Hoverver, when i connect MacBook using WiFi, is cannot detect any services hosted by Linux box. I can connect by manually entering IP address in "Connect to server" window, though.

The moment I plug ethernet cable, remote shares instantly show in Finder.

However connected, both devices are in same network, ping each other etc.

Can anyone help?

Click to expand...

mDNS stuff needs to be delivered at a minimum rate, for 2.4GHz network it is 12Mbps (so Cicso says). Ensure your connection is at least this fast. Also ensure that when on wifi you're not on a different network segment or netmask.

Bonjour only works between all machines on the same subnet.

WiFi can be on a different IP subnet range from a wired connection, leaving your WiFi Mac in a different subnet and thus unable to "see" the subnet where Bonjour is.


Different subnet means no Bonjour across both WiFi and Ethernet.

Sayer said:

Bonjour only works between all machines on the same subnet.

WiFi can be on a different IP subnet range from a wired connection, leaving your WiFi Mac in a different subnet and thus unable to "see" the subnet where Bonjour is.

Code:

Maybe Ethernet is: 192.168.1.xxx

Maybe WiFi is:     192.168.2.xxx

Different subnet means no Bonjour across both WiFi and Ethernet.

Click to expand...

it may not even be that, some routers now are blocking wifi from talking to ethernet for security sake, it's a setting called something like wifi segmentation or something like that

jmcgeejr said:

it may not even be that, some routers now are blocking wifi from talking to ethernet for security sake, it's a setting called something like wifi segmentation or something like that

Click to expand...

OP did say he could communicate directly through IP address, so it would have to be something more like blocking port 5353.

jared_kipe said:

OP did say he could communicate directly through IP address, so it would have to be something more like blocking port 5353.

Click to expand...

not necessarily, bonjour is a broadcast protocol, direct IP is not, some firewalls block broadcasting btw wifi and lan.

jmcgeejr said:

not necessarily, bonjour is a broadcast protocol, direct IP is not, some firewalls block broadcasting btw wifi and lan.

Click to expand...

Ok plausible then. Any particular router/brand that is doing this?

you probably have multicast on WiFi disabled

and as I said, your "router" is probably blocking multicast to/from WiFi

with no multicast, there is no mDNS, the m in mDNS being multicast...

with no mDNS there is no Bonjour...

you might want to try using Wireshark to see if you can see the mDNS packets

Hi,

I'm sorry for bumping this old(ish) thread, but I'm having the exact same problem with my MacBook Pro running Mountain Lion, only with the wired connection, not the wireless: when connected through WiFi all network devices show immediately in Finder, when connected through Ethernet cable, nothing is shown.
All devices are on the same subnetwork (192.168.1.x) and I've ruled out router configuration as the problem as a PPC Mac Mini running Leopard connected to the exact same Ethernet port in the router works as expected.

Were you able to solve your problem?
Any other suggestions?
Ethernet device configuration?

Thank you for any help you can provide

Renew DHCP Lease

I had this problem and the fix was this:

Network > Airport > Advanced > TCP/IP, and then click "Renew DHCP Lease" button.

It was clear my issue had only to do with my wi-fi connection, because when I plugged an ethernet cable to the router, bonjour worked.

Bonjour cannot be routed

I am having the same problem and found more information here.

Each query or advertisement is sent to the Bonjour multicast address for delivery to all clients on the subnet. Apple’s Bonjour protocol relies on Multicast DNS (mDNS) operating at UDP port 5353 and sends to these reserved group addresses:

IPv4 Group Address - 224.0.0.251
IPv6 Group Address - FF02::FB

The addresses used by the Bonjour protocol are link-local multicast addresses and thus are only forwarded on the local L2 domain. Routers cannot use multicast routing to redirect the traffic because the time to live (TTL) is set to one, and link-local multicast is meant to stay local by design.

Click to expand...

I wished that sort of info was provided by Apple at least. So far I don't have a solution though. Cisco's article suggests a dedicater router is required

Really sucks.

mDNS can be repeated!

After more research...

Some solutions are proposed on this post to route mDNS from the wifi subnet to the other one:
http://forum.pfsense.org/index.php?topic=59693.msg321412#msg321412

There Darell Tan wrote a mdns repeater for *WRT here:
mdns-repeater: mDNS across subnets

Joel Knight wrote something about this as well, specifically using AVAHI.
AirPlay, VLANs, and an Open Source Solution

And lastly, there are applications for windows and osx that can help you, as detailed here:
Bonjour/ZeroConf/Rendezvous/mDNS across multiple subnets

Click to expand...

such as running an mDNS-repeater daemon on the Wifi router... cool but not so straight-forward..