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I'm a Google Reader convert

My blog hasn’t had much to say recently, but now that I’m feeling pressured by University assignments, I think it’s time to get back into one-post-per-day mode :-)

I remember once trying Google Reader, just after it launched, and very quickly deciding that I couldn’t stand it, and I’d stick to Liferea.

Recently, however, Liferea has been giving me trouble. It’s been incredibly unstable, and I’d often forgot to run a transparent proxy on my laptop when in restrictive environments, so it’d miss lots of posts and generally be un-happy. The instability I fixed by exporting an OPML list, wiping the configuration, and re-loading, but that was a ball-ache to do. While I was bitching about this, Vhata pushed me to try Google Reader again.

I was pleasantly surprised. It works well, and I didn’t find it oppressive. That doesn’t mean it’s perfect, I’d like to see the following things improved:

  • Duplicate post detection (i.e. planetified & origional posts, liferea does this)
  • Performance
  • Favicons (or something similar, to make it more clear where a post comes from)
  • On that note, maybe configurable colour borders for important feeds?
  • Automatic refreshing (i.e. “r”)
  • More viewable area
  • A key press for opening a post in a backgrounded new tab “v” changes your focus to the new tab, which is against the principles of tabbed browsing.

Some cool things it does that lifera doesn’t:

  • Clicking on a folder shows you the all the posts from the feeds in that folder
  • “river of posts” view, which lets me get through my reading a lot faster
  • preloading images for posts that I haven’t got to yet (this contributes a fair whack to the reading speed, given the slow interwebs in ZA)
  • Shared items
  • Access from multiple machines (OX, X-forwarding worked, but this is neater)
  • Doesn’t crash (sorry lifrea…)

I’m converted. Google Reader really is good.

/me gets on with reading feeds…

That was *camp

I’m now sitting in Arniston, on a horribly slow GPRS connection, after *camp, which was this weekend, at AIMS. It was a BarCamp-like “unconference”, organised by the geekdinner crowd. I put off having the weekend at Arniston for *camp, and for me, I think that was worth it.

The event was really good. I haven’t been very involved in the organising, and didn’t come prepared with a talk (just equipment). At the start, it felt like there were never going to be enough talks to keep us going, but as soon as it started, it began rolling, and continued for 2 days. The talks were varied, from technical, to psychological, to practical. I was really impressed. The quality of the talks was quite high - I was rarely bored (although I did have IRC distractions).

As usual, I had Jonathan Carter’s camera, and videoed everything. I’m going to go home to around 8 hours of video that needs editing, synchronizing, encoding, and uploading to archive.org. It’ll take a while, guys, be patient.

Today, I got involved with setting up the lab for practical demos. We had 9 PCs lent, and needed Ubuntu on them. Of course, the natural approach is netinstall - I’m familiar with netinstalling Ubuntu, and it is a great way to set up a pile of computers. However, we ran into problem after problem.

  1. We were using dnsmasq (on my laptop) for DHCP and TFTP, but it wasn’t the router. So I set the router DHCP option. This seemed to break dnsmasq - PCs stopped accepting leases and DHCPDECLINED them. I’ve never seen that before. So I had to route through my laptop - no biggie.
  2. AIMS is behind a 400kbps connection, and while thy have an apt-cacher, it seemed badly seeded, and it looked like it was going to take us hours to install, so I went to my car and collected a set of Ubuntu archive DVDs that I happened to have on hand, and loaded them via a cluster of laptops and rsync ;-)
  3. Of course those DVDs didn’t have udebs on them (the debian-installer bits and pieces), so I had to quickly write a script to download all the udebs, and their necessary support structure.
  4. Now the machines netboot installed really fast, but at the very end of the install, it failed, due to some package signature problem.
  5. I ran debmirror, to ensure that my mirror was up to date, and it was. I ran the md5 sum checks, and they passed. I have no idea what the problem was.
  6. Eventually, the lab was installed with 3 install CDs, and then clubbed into shape with clusterssh. 5hrs or so after starting - what a waste of time, we should have started with CDs…

So, lesson for next time, test your netboot setup in advance, don’t assume that a mirror will be in working shape. We should have set up the lab on day one, for use on day 2.

The upshot of this is that I didn’t see any talks today (excepting a practical in the lab, on scribus, once it was up). I’ll have to watch the videos later.

Now, I’m going to enjoy a few days in Arniston, and then come home to graduate.

GeekDinner meets Linkedin

I’ve finally jumped on the Linkedin bandwagon. Amongst other things, I’ve added a GeekDinner Group.

Uncapped Local access

We’ve read that Telkom is implementing uncapped local access, as mandated by ICASA. The regulation states “local bandwidth shall not be subject to the cap”, but nobody seriously thinks Telkom will follow this to the letter. There is a huge market in inter-office VPNs over ADSL, and Telkom don’t want to lose out on that revenue stream.

Currently the savvy users out there use hacks like mine to least-cost-route local traffic over cheaper IS “Local-Only” accounts (like these). Hell, even ISPs route their clients’ local traffic over the IS Local-Only accounts.

From what I’ve heard from the friendly frogs, Telkom are really just going to keep it simple, and implement the equivalent of IS DSL accounts, where after you get capped, you get another, local-only cap. This can be implemented with Radius only, and will (to some extent) prevent the service from being abused be everybody.

So yes, we all still need our separate IS Local-Only accounts, and do our own LCR.

Anybody who thinks Telkom is doing any good for South Africa, go and sit in a corner now!

Local only DSL

This blog has been languishing - I’ve been busy. I’ve got some drafts that I need to finish up and post…

I’ve finally jumped onto the local only DSL bandwagon. If you haven’t done it yet, it’s a great way to save some bucks. The idea is that you get a local only account like this, which costs a fraction per GiB compared to normal account. Then you get your router to connect to both simultaneously, and route intelligently between them.

Most ADSL routers won’t let you connect 2 concurrent ADSL connections on the same ATM circuit. The solution is to use a separate modem and router. I’m using a basic Billion modem, in bridged mode, and a WRT54GL, running OpenWRT/kamikaze, as the router.

OpenWRT doesn’t support 2 PPPoE connections out of the box, but I’ve found the problems, and got a few changes committed upstream, that solve them:

The firewall needs to be modified with “WAN=ppp+” somewhere near the top, so that it masquerades all the ppp connections. This was a hack, apparently the firewall is being re-written soon.

There is also a bug that resets existing PPPoE connections on a ethernet interface when you fire up a new connection. This will apparently be fixed by the future interface aliasing support. For now, I just hacked around it in /lib/network/config.sh:

 prepare_interface() {
        local iface="$1"
        local config="$2"

       #SR: We don't want to reset any pppoe connections
        config_get proto "$config" proto
        [ "$proto" = "pppoe" ] && return 0

and /sbin/ifdown:

config_get ifname "$cfg" ifname
config_get device "$cfg" device

[ ."${proto%oe}" == ."ppp" ] && device=
[ ."$device" != ."$ifname" ] || device=
for dev in $ifname $device; do
       ifconfig "$dev" 0.0.0.0 down >/dev/null 2>/dev/null

I got my local routes list from alm.za.net, saved it as a list in CDIR format. OpenWRT already has a static routing configuration system, but it’s very verbose. So I wrote my own, adding the new configuration option routefile. I used these hotplug scripts to set up routing and source routing, with the help of iproute2:

$ ipkg install ip

$ mkdir /etc/localroutes
$ wget http://alm.za.net/ip/localroutes4.txt -O - | awk '{print $4}' > /etc/routes/localroutes

$ cat /etc/config/network
# ...local interfaces...

#### WAN configuration
config interface    wan
    option ifname   "eth0.1"
    option proto    pppoe
    option username "xxxxx@international.co.za"
    option password "xxxxxx"
    option routefile "/etc/routes/exceptions"
    option defaultroute 1

config interface    localdsl
    option ifname   "eth0.1"
    option proto    pppoe
    option username "xxxxx@local.co.za"
    option password "xxxxxx"
    option routefile "/etc/routes/zaroutes"
    option defaultroute 0

$ cat /etc/iproute2/rt_tables 
#
# reserved values
#
255     local
254     main
253     default
0       unspec
#
# local
#
1   wan
2   localdsl

$ cat /etc/hotplug.d/iface/20-split-routes
case "$ACTION" in
    ifup)
            . /etc/functions.sh
            include /lib/network
            scan_interfaces
            config_get routefile "$INTERFACE" routefile

            # Does this interface have custom routes?
            if [ -e "$routefile" ]; then

                    # Add routes for this interface
                    cat "$routefile" | while read route; do
                            ip route add "$route" dev "$DEVICE"
                    done

                    # Set up source routing
                    peer=`ip addr show dev $DEVICE | sed -n '/inet/ s#.* peer \([0-9.]*\)/.*#\1# p'`
                    address=`ip addr show dev $DEVICE | sed -n '/inet/ s/.* inet \([0-9.]*\) .*/\1/ p'`

                    ip route add "$peer" dev "$DEVICE" src "$address" table "$INTERFACE"
                    ip route add default via "$peer" table "$INTERFACE"
                    ip rule add from "$address" table "$INTERFACE"
            fi

            # Make sure this interface is present in all the custom routing tables:
            route=`ip route show dev "$DEVICE" | awk '/scope link  src/ {print $1}'`
            awk '/^[0-9]/ {if ($1 > 0 && $1 < 250) print $2}' /etc/iproute2/rt_tables | while read table; do
                    ip route add "$route" dev "$DEVICE" table "$table"
            done
    ;;
esac

$ cat /etc/hotplug.d/net/20-split-routes
case "$ACTION" in
        register)
            . /etc/functions.sh
            include /lib/network
            scan_interfaces

            # If this interface doesn't have a link local route, we don't need to bother
            route=`ip route show dev "$INTERFACE" | awk '/scope link  src/ {print $1}'`
            [ ."$route" = ."" ] && return 0

            # Add this interface's route to all custom routing tables
            awk '/^[0-9]/ {if ($1 > 0 && $1 < 250) print $2}' /etc/iproute2/rt_tables | while read table; do
                    ip route add "$route" dev "$INTERFACE" table "$table"
            done
    ;;
esac

Now, lastly, it won’t bring up both interfaces by default. That will be fixed by aliasing in the future, but for now:

$ cat /etc/init.d/network-multiwan
#!/bin/sh
ifup wan
ifup localdsl

$ chmod 755 /etc/init.d/network-multiwan
$ ln -s ../init.d/network-multiwan /etc/rc.d/S49network-multiwan

That’s it, and it’s working beautifully :-)

What is source routing, people ask? The problem is that your router now has 2 WAN IP addresses. IP1 is used for local traffic, and IP2 for international. So if somebody in ZA tries to connect to IP2, the reply (local destination) will go out of Interface 1. The ISP on the other end of Interface 1 will drop this reply, because it’s not coming from IP1.

Source routing tells the router that replies must go out of the same interface that the request came in on. I’m doing it by creating separate routing tables for traffic origionating from each WAN interface.

Gotchas

  • If you are using 2 different ISPs (say SAIX international and IS local), you must make sure that DNS queries get routed out the right interface. SAIX won’t accept queries on their servers from IS, and vice versa.
  • SAIX Web proxies, Mail servers, and News servers don’t accept traffic from local accounts. (especially from another ISP)

In Portland for Ubuntu Live

Ubuntu Live kicks off tomorrow in Portland, OR, USA, back to back with OSCON.

The tale of air travel

I left London yesterday morning (after my brother accidentally woke me up an hour early), and almost didn’t make it out of Gatwick - due to terrible weather, all flights were delayed, and many cancelled. I went through the Trainee security queue, and they all ogled my laptop bag on the Xray machine (filled to the brim with interesting equipment, power supplies, and adaptors, as usual). The lad who frisked me was clearly very green, and I don’t think I could have got an unauthorised toothpick through ;-) Thankfully I wasn’t picked out for “special attention” again after that, although maybe 10% of people got taken away from the Immigration queue, in at Newark, New York. It’s quite a scary process - the queue moves very slowly, because everyone gets interviewed for 2-10 minutes. People with children get a long interview, and if you didn’t dot every I and cross every T on your forms, you get sent away, dismissively. Then, as I said, about 10% of passengers fail their interview (or are just unlucky), their papers are put in a big, zip lock bag, and the immigration official shouts for an “ESCORT!” to take them away, down the white corridor, from whence we presume they will never return… There were only 2 escorts, and they were working flat out…

Oh, btw, I’m a huge fan of the air power wiki. My laptop has a negligible battery life, and likes being tethered to the mains. Talking of which, on the 767 from London to New York, there were 110V power sockets under the seats - w00t :-)

My plane to Portland was packed, and delayed for almost 2hrs, in the Friday rush. :-( But I got there mostly on time, and crawled into my hotel bed before midnight, after, literally, a 24hr day. The hotel is dingy, but cheap & clean. And right next door to the convention centre, and a MAX tram stop.

The tale of dodgy wifi

I get free wifi from the Hotel across the street (they have an agreement with mine), but it’s dodgy as hell. It just dies without warning, and when it’s dead, it’s AP seems to cause havoc (when I try and associate with other networks, I always end up connecting to it).

Portland has a free MetroFi service, ad-supported. Which sucks - badly. The signal is mostly pretty poor (I can only get it with my laptop screen right against the window in my room), and when I’m around the town there is normally little signal. They’ve spread their APs over all 4 non-overlapping channels, polluting the spectrum. When you do have signal, the ad system means you get lots of 302 redirects, which don’t agree with my RSS reader, or me. I find myself proxying out over an SSH tunnel, for my sanity. :-( MetroFi—

Portland so far

Portland is nice enough. There is free public transport inside the city centre, it’s leafy, and the people seem friendly enough. But I haven’t really got a feel for it yet.

I poked around the Saturday market this morning, which could have been just about anywhere in the world (excepting the men selling US flags, and almost all the stalls having credit card facilities :-) ). Some nice work, and some good food (I had a spectacular omlette). I left when it started raining.

I went to see the Body Worlds 3 exhibition at the Oregon Museum of Science and Industry. Very interesting. You get a good feeling for human anatomy and muscle structure. The exhibits of tumours and healthy body parts were quite enlightening. The posed, plastinated cadavers got rather repetitive, although all well worth a close look. I found the exhibits of blood vessels only to be the most beautiful. But overall, I didn’t find it to be as mind-blowing or offensive as the media has made it out to be.

Tonight, I’m off to find some fellow Ubuntu Live’ers, unless the Jetlag gets to me first.

Lighttpd mod_rewrite

I’ve migrated my teeny-weenie Xen web/mail server to Debian/etch. It hasn’t even been rebooted (it would be a shame to spoil the uptime :-) ):

$ uprecords
     #               Uptime | System                                     Boot up
----------------------------+---------------------------------------------------
->   1   198 days, 06:16:44 | Linux 2.6.16.13-xenU      Thu Oct 12 10:12:51 2006
     2    99 days, 19:25:00 | Linux 2.6.12-xenU         Sun Oct  9 03:58:58 2005

It runs Lighttpd, a small and fast little webserver, popular in the Rails world. Lighttpd with PHP-fastcgi is probably faster than apache, and uses much less RAM.

With etch, I’ve finally been able to get mod_rewrite to work. So my Zapiro archive has nice URLs now :-)

Lighttpd has a very nice configuration style:

# No WWW
$HTTP["host"] =~ "^www\.((.+\.)?rivera\.za\.net)$" {
  url.redirect = ( ".*" => "http://%1$1" )
}
# Add WWW:
$HTTP["host"] =~ "^((foobar|someclient)\.co\.za)$" {
  url.redirect = ( ".*" => "http://www.%1$0" )
}

############################################
# PHP Apps:
$HTTP["host"] =~ "^(zapiro\.rivera\.za\.net)$" {
  url.redirect = ( "^/\?/(.*)" => "http://%1/$1" )
  url.rewrite-once = ( "^/(feed)$" => "/index.php?/$1",
                       "^/([0-9]+/[0-9]+/[0-9]+)$" => "/index.php?/$1" )
}

It’s more logical than apache, but you have to watch out for rewrite->redirect->rewrite loops. So if you change to a clean URL syntax, you can’t put in rewrites from index.php?/uglurl to /uglyurl because /uglyurl rewrites back to /index.php?/uglyurl, and you get a loop :-)

More ClugPark work

Well, we’ve now got a custom theme for http://park.clug.org.za/ (by superfly, thanks!) I still want to hack planetplanet to death, but that can wait until they decide on their direction…

In the meantime, I’ve been brushing up my mediawiki hacking for the ClugPark gallery. Mediawiki is a monster! The select query looks like this:

$select = "SELECT page_namespace, page_title, old_text, img_description "
          . "FROM " . $dbr->tableName('page') . " "
          . "LEFT JOIN " . $dbr->tableName('revision') . " ON page_latest = rev_id "
          . "LEFT JOIN " . $dbr->tableName('text') . " ON old_id = rev_text_id "
          . "LEFT JOIN " . $dbr->tableName('image') . " ON page_title = img_name "
          . "INNER JOIN " . $dbr->tableName('categorylinks') . " "
          . "ON page_id = cl_from AND cl_to = " . $dbr->addQuotes($catKey) . " ";
$where = " WHERE page_namespace = " . $wgContLang->getNsIndex('Image') . " "
         . "ORDER BY page_title ";

Yup. Lovely stuff. Anyway, when I’m happy with the extension, I’ll post it somewhere… (Same goes for my other mediawiki extenisons)

ClugPark

I’ve been doing some themeing work on Clug Park, and it’s pretty much ready to go now. It could still do with some theming work, and probably some more blogs (I bet there are other blogging CLUGgers out there).

It seems that PlanetPlanet might switch to an entirely re-written version of it’s software. That shouldn’t be a problem, I think the themes are still compatible.

We’ve hacked our planet to always display 2 entries from every member. If we switch, the hack will have to be ported. Which isn’t a bad thing, I don’t want to pass the patch upstream if planetplanet is about to switch to another trunk, anyway :-)

Google Webmaster Tools

After reading the slashdotted google hacked sites fiasco, I (and by the look of it, the rest of the Internet) decided to check out Google Webmaster tools.

Verifying all my sites was a pain (the verification server probably got slashdotted, and when it was working, it wasn’t resolving DNS properly), and took about a week. But now that that’s over, it gives me some useful info. It really helps, to get a view of your site, as google sees it.

Most of the use for me, is the Preferred Domain tool (i.e. make google prefer www.yoursite.com over yoursite.com), and the Site Content tool.

I’ll look into sitemaps another time :-)

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