Diff for "PlayDay20130209" - Personal Telco Project

Differences between revisions 4 and 6 (spanning 2 versions)

Location: NodeWorldCup
Date and Time: Saturday, February 9, 2013, Noon to 5pm
Scribe: You
Roll Call: Them

Agenda

Set up wifi meshes using openwrt and batman-adv on UbiquitiAirRouters and AcctonMR3201A
Bring your laptop
Bring your OpenWrt'able router
Does anyone have a whiteboard they can bring?
Or look over the shoulder of others

Notes

Stuff Russell is bringing:
- 1x whiteboard (thanks cseppa!)
- 15x Accton MR3201A's with antennas and power supplies
- 15x cat5 cables (flat white ones we received with the routers)
- 1x 16-port 10/100 ethernet switch with power supply
- 1x Buffalo WZR600DHP configured to provide ethernet from NodeWorldCup wifi and also enable parallel flashing of Acctons
- 2x power strips

Flashing Base OpenWrt onto Accton MR3201A: The Accton MR3201A devices have rather slow flash, and as a result, writing an image to them takes a considerable amount of time, approximately 15 minutes. In order to speed that process up, I configured a Buffalo WZR600DHP to flash 4 of them in parallel. The Buffalo was chosen because it has enough flash space of its own to persistently store the base image that is flashed on the Accton, and it has 4 LAN ports that can be configured as distinct interfaces. On the Buffalo, I used a basic Ar71Cab image, with the addition of the ap51-flash package and a custom configuration.

Buffalo flasher configuration changes

/etc/config/network:

switch configuration:

config switch
        option name 'eth0'
        option reset '1'
        option enable_vlan '1'

#config switch_vlan
#        option device 'eth0'
#        option vlan '1'
#        option ports '0 1 2 3 4'

config switch_vlan
        option device 'eth0'
        option vlan '1'
        option ports '0t 1'

config switch_vlan
        option device 'eth0'
        option vlan '2'
        option ports '0t 2'

config switch_vlan
        option device 'eth0'
        option vlan '3'
        option ports '0t 3'

config switch_vlan
        option device 'eth0'
        option vlan '4'
        option ports '0t 4'

network interfaces:

config 'interface' 'lan1'
        option 'ifname' 'eth0.1'
        option 'proto' 'static'
        option 'ipaddr' '192.168.11.1'
        option 'netmask' '255.255.255.0'

config 'interface' 'lan2'
        option 'ifname' 'eth0.2'
        option 'proto' 'static'
        option 'ipaddr' '192.168.12.1'
        option 'netmask' '255.255.255.0'

config 'interface' 'lan3'
        option 'ifname' 'eth0.3'
        option 'proto' 'static'
        option 'ipaddr' '192.168.13.1'
        option 'netmask' '255.255.255.0'

config 'interface' 'lan4'
        option 'ifname' 'eth0.4'
        option 'proto' 'static'
        option 'ipaddr' '192.168.14.1'
        option 'netmask' '255.255.255.0'

/etc/config/dhcp add interfaces:

#config dhcp priv
#       option interface        priv
#       option start            100
#       option limit            150
#       option leasetime        12h

config dhcp lan1
        option interface        lan1
        option start            10
        option limit            200
        option leasetime        1h

config dhcp lan2
        option interface        lan2
        option start            10
        option limit            200
        option leasetime        1h

config dhcp lan3
        option interface        lan3
        option start            10
        option limit            200
        option leasetime        1h

config dhcp lan4
        option interface        lan4
        option start            10
        option limit            200
        option leasetime        1h

create and populate /src with Accton image files:

-rw-r--r-- 1 russell users    1411 Feb  8 17:59 md5sums
-rw-r--r-- 1 russell users 2949120 Feb  8 17:59 openwrt-atheros-combined.squashfs.img
-rw-r--r-- 1 russell users 1966080 Feb  8 17:59 openwrt-atheros-root.squashfs
-rwxr-xr-x 1 russell users 2844736 Feb  8 17:58 openwrt-atheros-vmlinux.elf
-rw-r--r-- 1 russell users 1310720 Feb  8 17:58 openwrt-atheros-vmlinux.gz
-rw-r--r-- 1 russell users  917504 Feb  8 17:58 openwrt-atheros-vmlinux.lzma

add ap51-flash package to Buffalo

Flashing Accton's:
- associate with MeshPlayDay
- connect ethernet cables between the 4 LAN ports on the Buffalo and the Acctons
- connect de-energized power strip's power supplies to the Acctons
- login to Buffalo, N times (where N <= 4): ssh root@10.11.25.1
- in each shell:
```
cd /src 
ap51-flash eth0.N openwrt-atheros-root.squashfs openwrt-atheros-vmlinux.lzma
```
  where N is the LAN port number
- when each shell's ap51-flash has started, energize the power strip
- confirm each of the ap51-flash's has detected its Accton and has begun flashing
- wait about 15 minutes for ap51-flash to complete, the Accton to reboot, and the firstboot sequence to complete
- for each Accton:
  - remove the Accton from the ethernet cable
  - connect to a laptop via ethernet (with a staticly configured 192.168.1.2/24 interface)
  - confirm that the Accton answers telnet at 192.168.1.1.

The above is for reference. Russell has pre-flashed the Acctons as far as this. The remainder of the notes indicate the steps needed to install and configure batman-adv on the Accton's to participate in a mesh.

configure Accton:

turn off firewall
```
/etc/init.d/firewall disable
```
turn off dnsmasq
```
/etc/init.d/dnsmasq disable
```
set a password (this will disable telnet, so remember the password you give it!)

edit /etc/config/system to assign a hostname (helps to remind you what device you are logged into)

config system
        option hostname 'meshnode-11-2'
        option timezone 'PST8PDT'

edit /etc/config/wireless

vi /etc/config/wireless

enable the radio
```
# option disabled 1
```

set a unique SSID for the ap mode

config wifi-iface
        option device   radio0
        option network  lan
        option mode     ap
        option ssid     meshnode-11.2    
        option encryption none

configure network interfaces to either dynamic or static so that you can log in to the device *and* reach package archives on the internets (if dynamic, configure upstream router to provide a consistent ip address)
```
vi /etc/config/network
```
```
config interface lan
        option ifname   eth0
        option type     bridge
        option proto    static
        option ipaddr   192.168.11.2
        option netmask  255.255.255.0
        option gateway  192.168.11.1
        option dns      192.168.11.1
```
Note that the SSID in the step above was derived from the static IP address assigned here, that way we can tell what we are connecting to. The network is derived from a the network I was connected to when I did this configuration, we may want to choose 10.11.25.x during the playday, but it should correspond to the network the device is connected to while configuration is performed. It is important to coordinate the IP addresses you are assigning. If you assign a static IP address, please WRITE IT ON THE WHITE BOARD so others can see what is already in use!
reboot
ssh in
```
ssh root@192.168.11.2
```
confirm you can get to the internets from the Accton
```
ping 8.8.8.8
ping google.com
```

fix /etc/opkg.conf, the first line should be this:

src/gz barrier_breaker http://iris.personaltelco.net/~russell/openwrt/r35525-atheros

update package metadata (the metadata is stored to a RAM-based filesystem, so it must be repeated after a reboot if you want to install more packages)
```
opkg update
```

install batman-adv:

opkg install kmod-batman-adv

you should see:

Installing kmod-batman-adv (3.3.8+2013.0.0-2) to root...
Downloading http://iris.personaltelco.net/~russell/openwrt/r35525-atheros/kmod-batman-adv_3.3.8+2013.0.0-2_atheros.ipk.
Installing kmod-lib-crc16 (3.3.8-1) to root...
Downloading http://iris.personaltelco.net/~russell/openwrt/r35525-atheros/kmod-lib-crc16_3.3.8-1_atheros.ipk.
Installing kmod-crypto-crc32c (3.3.8-1) to root...
Downloading http://iris.personaltelco.net/~russell/openwrt/r35525-atheros/kmod-crypto-crc32c_3.3.8-1_atheros.ipk.
Installing kmod-crypto-hash (3.3.8-1) to root...
Downloading http://iris.personaltelco.net/~russell/openwrt/r35525-atheros/kmod-crypto-hash_3.3.8-1_atheros.ipk.
Installing kmod-lib-crc32c (3.3.8-1) to root...
Downloading http://iris.personaltelco.net/~russell/openwrt/r35525-atheros/kmod-lib-crc32c_3.3.8-1_atheros.ipk.
Configuring kmod-crypto-hash.
Configuring kmod-lib-crc16.
Configuring kmod-crypto-crc32c.
Configuring kmod-lib-crc32c.
Configuring kmod-batman-adv.

(optional) install some other useful tools:
```
opkg install wireless-tools iwinfo ip
```

add a mesh interface to /etc/config/wireless:

config wifi-iface
        option  device  radio0
        option  ifname  adhoc0
        option  network mesh        
        option  mode    adhoc                
        option  ssid    ptp-mesh                        
        option  encryption none

this interface needs a larger than normal MTU to accomodate the batman-adv wrappers, so add this stanza to /etc/config/network:

config 'interface' 'mesh'
        option 'ifname' 'adhoc0'
        option 'proto' 'batadv'
        option 'mtu' '1528'
        option 'mesh' 'bat0'

add bat0 to the lan bridge in /etc/config/network

config interface lan
        option ifname   "eth0 bat0"
        option type     bridge
        [...]

logout and disconnect
repeat for next Accton, then plug in power-only to previously configured Accton and see if you can ping it over the mesh
do a happy dance

Note, you should avoid having multiple nodes participating in the same mesh and connected to a common ethernet network at the same time (at least historically), for fear of bridge loops (packets going around in circles until the network melts). If there are multiple teams working on separate meshes, choose different wireless channels (defined in the first stanza of /etc/config/wireless).

Open Questions:

what do all those options in /etc/config/batman-adv mean?
does bridge loop avoidance really work?
when your mesh is complete, pick a device to be vis_mode server and then look at the batctl vd dot, what does it look like?
why isn't the wireless interface getting added to the bat0 mesh interface?

[CategoryMeetingNotes]

-  ← Revision 4 as of 2013-02-09 03:24:15 →
  Size: 11034
  Editor: RussellSenior
  Comment: pad out the lesson plan
+  ← Revision 6 as of 2013-02-09 04:11:59 →
  Size: 10964
  Editor: RussellSenior
  Comment: fix a typo
-Deletions are marked like this.
+Additions are marked like this.
 Line 244:
+        option  ifname  adhoc0
-Line 252:
+Line 253:
-        option 'proto' 'none'
+        option 'ifname' 'adhoc0'

        option 'proto' 'batadv'
-Line 254:
+Line 256:
-}}}

  a. insert an "interfaces" line in /etc/config/batman-adv

  {{{

config 'mesh' 'bat0'

 option 'interfaces' 'wlan0-1'

 option 'aggregated_ogms'

        [...]
+        option 'mesh' 'bat0'