[Commotion-admin] [Commotion-OpenWRT - Feature #447] (Feedback) Auto set-up all ethernet interfaces, not just eth0

[Andy Gunn]

Sorry to take so long to get back to y'all on this, but I have a thought.

How much autodetection behaviour will be irrelevant or bypassed with the
new Quickstart process?

For example, if I select that I don't want to share my bandwidth, will
it turn the DHCP client off on the Ethernet port? Or is there other
behaviour that will be pre-empted by the generated or uploaded
configurations?


On 02/05/2013 05:50 PM, commotion-admin at lists.chambana.net wrote:
> Issue #447 has been updated by Josh King.
> 
>   * *Status* changed from /New/ to /Feedback/
>   * *Assignee* set to /Josh King/
> 
> It's not that straightforward. It's not a misconfiguration, but it's
> true that Commotion currently lacks that capability. I'll try and
> explain below, and then elicit some feedback:
> 
>   * We currently don't deal with trying to autoconfigure more than one
>     interface at a time, because it requires more sophisticated handling
>     of bridged interfaces than we currently have. PR3 added support for
>     bridges, but it basically just doesn't obliterate them, not handle
>     them specially. Since autoconfiguring multiple ports would make it
>     unclear what IPs or IP subnets should be assigned (just increment
>     them forever? do we have to adjust DHCP handouts so we don't step on
>     our own addresses? Doesn't seem extensible), we would probably
>     establish a LAN bridge and add all LAN interfaces to that. We would
>     need to add or remove automatically configuring interfaces from the
>     bridge depending on whether it's a gateway, given that we want the
>     bridge to only be offering DHCP addresses, not requesting them. The
>     scripts just don't do that at the moment, and it's tricky to get
>     them to since there are all sorts of hidden manual checks and
>     handling for things like bridge interfaces, and since the old
>     network scripts are not very stateful it's slightly tough to modify
>     a bridge on the fly. This might be easier with Attitude Adjustment.
> 
>   * It's not clear what the default behavior should be. Do we try by
>     default to detect gateways on all interfaces? We can request
>     multiple addresses, but we can only have one valid gateway at a
>     time. If a new interface gets plugged and receives a valid address,
>     does that mean that the other gateway interface gets clobbered?
> 
> My opinion is that the default behavior is that the first ethernet
> interface is autodetecting, and then all the others get added to a LAN
> bridge and just hand out leases, and other situations would have to be
> configured at least somewhat manually. This most closely mimics how
> routers work by default, with a WAN port and several LAN ports. However,
> this would actually NOT address the use case you're suggesting
> automatically, so I'd like to ask for more feedback on what we think the
> default use case should be.
> 
> ------------------------------------------------------------------------
> 
> 
>   Feature #447: Auto set-up all ethernet interfaces, not just eth0
>   <https://code.commotionwireless.net/issues/447#change-1177>
> 
>   * Author: Preston Rhea
>   * Status: Feedback
>   * Priority: Normal
>   * Assignee: Josh King
>   * Category:
>   * Target version:
> 
> As I understood from my conversation with Will, the Commotion set-up
> script only automatically configures the primary ethernet interface on
> NanoStations. We talked it through and, from the field team's
> perspective, we think it would be best for the script to execute the
> same steps and configuration process that runs for eth0 on every
> ethernet interface a device has.
> 
> Commotion never automatically includes eth1. Will does not know where
> the mis-configuration happens - it may be disabled, or the software may
> lack this capability presently.
> 
> Here's the whole conversation output:
> 
> The primary port is eth0, and Commotion automatically includes and turns
> this port on by default. However it does not automatically turn on eth1,
> even when there is a secondary port present.
> 
> To search for and change / establish interfaces, one must enter
> etc/config/network filesystem. This file is processed by the Commotion
> scripts for mesh, commotionwireless.sh. However, actually establishing
> the interface take places at the OS / kernel level (Commotion OpenWRT in
> this case). If one runs ifconfig, they will not necessarily see eth1
> because it is down or not on, but running ifconfig eth1 will show its
> information.
> 
> It seems Andy had a script to add in at the bottom of the Commotion GUI
> to add in Power over Ethernet (PoE) electricity passthrough for the
> secondary port. To date, pasting this script in the GUI is the method to
> get the secondary port of NanoStations passing power. Once this change
> is made, the node must power cycle and reboot.
> 
> Following this, eth1 must be set as a dynamic, not static, interface to
> accept whatever IP address its gateway will give it. In this case, the
> NanoStation Loco daisy-chained to the secondary port on the Commotion
> NanoStation is the gateway node, so the secondary port (eth1) on the
> Commotion NanoStation is the gateway port. From this point forward, that
> Commotion NanoStation announces itself as a gateway to the rest of the mesh.
> 
> Finally, Will put eth1 in the WAN firewall zone. Thus, when traffic
> comes through, it can go out the WAN through to the mesh. This happens
> by default on eth0, but when we add eth1, we have to instruct it to
> allow traffic to pass through WAN.
> 
> ------------------------------------------------------------------------
> 
> You have received this notification because you have either subscribed
> to it, or are involved in it.
> To change your notification preferences, please click here:
> http://code.commotionwireless.net/my/account
> 

-- 

Andy Gunn
Field Engineer, Open Technology Institute
New America Foundation
202-596-3484
http://oti.newamerica.net