Sherman Heights, San Diego
Sherman Heights (zip 92102) is our 2nd neighborhood and third access point location - and the first officially built by SocalFreeNet.
Installation of the hardware was recently completed. Feb 11 update: Software configuration is complete and the node is fully operational.
Full Report
A group of 3 SDWUG members met at 10am to start the installation. Based on our previous site survey we planned to install our shiny new standard access point in a relay configuration. I.e. two radios, one to pick up service from our existing (premier!) Golden Hill node, and another to rebroadcast it. Note that we use separate radios due to the potential interference issues found by the NoCat and as discussed elsewhere.
This install was a little premature in that we still had software issues to resolve and were waiting on a replacement radio via Saturday delivery that hadn't arrived yet, but it was otherwise good timing for the building owner whose electrician was going to be around. So with a lot of last minute scurrying around for odds and ends, we optimistically gathered to see how far we could get. Fortunately physical access didn't involve ladder climbs like previous installs!
Physical installation went well but quickly stalled when our relay radio couldn't connect to the Smartbridge AirpointPro about 5/8 mile away but could connect to the other radio we were installing. We were perhaps a little sidetracked by this, as we'd previously had a problem with a Smartbridge in bridging mode to a Cisco 350 AP. After Lee (longtime SDWUG member and general wireless guru) arrived he quickly led us down the right path.
He suggested we start eliminating other variables in the chain: antenna, cable, radio card. This is where having two of everything onsite is a real lifesaver! We knew the antenna and its orientation were good as we'd aligned it using signal strength readings from Netstumbler. We swapped cables with no difference. Finally we deduced that the radio card was getting close APs but not further ones. Putting the case lid on/off and re-orientating it confirmed this.
As we'd by now fetched the (two!) Saturday Fedex and UPS deliveries of miniPCI radio cards (from Netgate.com and wisp-router.com, rather than mess with the radio and the delicate U.FL connector, we installed one of the new radios and reconnected it - hoping to eliminate either the pigtail or radio this way. It worked! Finally, about 3 hours into the install, our relay radio could connect to the base station!
The AP radio and antenna install was a breeze by comparison. With m0n0wall trivially setup to bridge the eth0 LAN port to the wi0 wireless card, it was soon providing reliable (albiet slow) access from Lee's laptop.
The next job was to string CAT5 from each radio back to a common point where we could provide power using our home-brew POE adapters and link the two radios via a crossover cable. We didn't have the proper mounting clips and had to make do with bent over nails. We're have to go back and finish that, along with hooking up the lightning protectors to a good ground.
Software Config
The next task was to get the software configured. We'd pre-configured m0n0wall for the relay radio to provide dhcp, firewall and routing services (with NAT disabled of course) rather than a pure bridge. Unlike our other two APs in the area which are pure bridges, we'd like to start subnetting and reap the management benefits including easier stats collection, ability to change routing as other APs come online etc.
We succeeded in getting outgoing connections, but not for more than one user at a time. Our internet access is provided through another Soekris running
MikroTik's RouterOS which provides captive portal and bandwidth management (eventually we hope our project to add captive portal to m0n0wall replaces this). Each successive user cut off the previous user. Our current thinking is that there is some setting in the captive portal that needs to be adjusted for this.
As laptop batteries started draining and families started calling, we packed up. The node is operating, sort of, but much fine tuning remains!
Lessons Learned
We knew this one going in, but its hard to stress the importance of verifying and validating all equipment under real conditions before trying to install it. E.g., the relay radio associated fine in all tests prior - but in hindsight we were always within a few metres of the AP with the metal lid off!
The physical design of the AP isn't perfect. E.g. we put the bulkhead female N connector in a place where its easy to damage when mounting the box. Its also a much deeper box than needed. Otherwise though, we're happy with the enclosure for this climate (and especially the $14 price!).
Physical proximity is no substitute for a good site survey. Our link relay quality is so far a little disappointing. A 'netgear' AP is a about 30 degrees away on the same channel as our distant 'base' AP. This plus perhaps the two trees between us and the cheesy 5 dBi omni at the base AP (another long story), combine to make the signal strength and quality vary between -38-60dBm and 50-90% respectively. Time will tell how effective this is (plus we can likely tune the antenna pointing a little more).
Things we did right
Overall this was a very smooth install. We had all the parts we needed (except U-clips for the cat5 cable), good diagnostic tools and we left at the end of the day with a $1000 hanging off the walls and a (mostly) working system. Several things we did helped this happen.
Two of everything. One nice, mostly unforeseen, result of deciding to separate radios is that we had two of almost everything. This makes it really easy to swap pieces back and forth to eliminate problems.
M0n0wall is a great software choice. Its small (<8MB), fast, reliable and, most of all, easy to configure. The GUI is a snap. Everything is saved in a single XML file. We were able to rewrite the flash a couple of times to get to a known working default and then either reload the config file or just tweak via the web interface.
Our standard AP project looks good so far, though more expensive than we'd like. E.g., our AP is essentially a $300 dumb bridge. We might be able to better than this in the future - at the expense of having two of everything, bummer.
Closing Words
A big thanks to the building owner who made this node possible. Without his excellent location (did you see that view?) and funds (assuming he pays the bill :->), this node wouldn't have been possible.
And of course, many thanks to the SDWUG folks who made this possible and so enjoyable! Especially master welder Matt, and master debuggers Lee and Chris.