avahi malfunctions on a machine connected to the network via multiple interfaces
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| avahi (Ubuntu) |
Confirmed
|
Critical
|
Unassigned | ||
| network-manager (Ubuntu) |
Confirmed
|
High
|
Unassigned | ||
Bug Description
I have a router making up one local NAT network connected to the internet. The router allows to connect both wired and wireless. My laptops are configured to use both wired and wireless. So I can walk around with them and also connect to the quicker wired network if they are on the desk.
Problem is that when the laptops are on my desk and I plug in the network cables they stay connected on wireless and so they get connected twice, wired and wireless, with two IP addresses, appearing as two computers for the router and all other computers in the network. Most things still simply work, like accessing the internet from the laptops, SSHing to another computer, ... what causes problems is Bonjour/mDNS. Avahi broadcasts available services (I have shared CUPS printers on the laptops) into the network, using the host name of the machine assigned on installation, for example "till-lenovo". As the broadcasts go through two interfaces there is a service name conflict and it seems that Avahi tries to overcome it by using host names like "till-lenovo-1", "till-lenovo-2", ... When the laptop keeps running one sees in the "avahi-discover" output on another machine the entries from the laptop, but with host names (and so the service names) changing from time to time. This leads to a client with a print queue pointing to a printer shared by the laptop via the printer's Bonjour service name cannot print any more.
I have done a short test and Avahi stops adding numbers to the original host name when turning off wireless on the laptop so that it connects only through the wired network.
One way of fixing (or working around?) the problem would be a change in network-manager to automatically turn off wireless if the computer is connected to a wired network and switching wireless back on when the network cable gets disconnected. This would probably also solve problems with other server functionality. --->> http://
Another solution would be a change in Avahi, somehow recognizing that the broadcasts through the two interfaces come from the same computer and so they can (and should) have the same service names, or recognizing that the two interfaces go into the same network and therefore broadcast only through one of them, stopping the broadcasting through the weaker one (the wireless in our case).
| Changed in avahi (Ubuntu): | |
| importance: | Undecided → High |
| Changed in network-manager (Ubuntu): | |
| importance: | Undecided → High |
| Changed in avahi (Ubuntu): | |
| milestone: | none → ubuntu-13.04-feature-freeze |
| Changed in network-manager (Ubuntu): | |
| milestone: | none → ubuntu-13.04-feature-freeze |
| Thomas Hood (jdthood) wrote | #1 |
| summary: |
- network-manager should not allow a computer to access the same network - by both wired and wireless - this especially breaks Bonjour/mDNS + avahi malfunctions on a machine connected to the network via multiple + interfaces |
| Till Kamppeter (till-kamppeter) wrote | #2 |
| Changed in avahi (Ubuntu): | |
| importance: | High → Critical |
| Launchpad Janitor (janitor) wrote | #3 |
| Changed in avahi (Ubuntu): | |
| status: | New → Confirmed |
| Changed in network-manager (Ubuntu): | |
| status: | New → Confirmed |
| psamuel (persaudsamuel) wrote | #5 |
| Carlos Luna (caralu1974) wrote | #6 |
| Carlos Luna (caralu1974) wrote | #7 |
| summary: |
- avahi malfunctions on a machine connected to the network via multiple - interfaces + Order Xanax Online:: avahi malfunctions on a machine connected to the + network via multiple interfaces |
| description: | updated |
| summary: |
- Order Xanax Online:: avahi malfunctions on a machine connected to the - network via multiple interfaces + avahi malfunctions on a machine connected to the network via multiple + interfaces |
| description: | updated |
| Stefan Grotehans (stefan-grotehans-b) wrote | #8 |
It's avahi that needs to be fixed.