google me: sendfile problems

After upgrading an ubuntu LTS server at work proftpd (not my choice) would not transfer files anymore. It would die with:

error using sendfile(): [75] Value too large for defined data type

After searching a little I found the problem: sendfile does not work if the filesystem on which the files are stored is 'special'. Of course we are serving files from a CIFS directory... Sigh.

On the legality of hacking the iPhone

The Belgian minister for Economy was seen with an iPhone recently. However Apple does not sell these things in Belgium.

So he got a little call from a journalist, according to him the only entity that could make him stop using a liberated iPhone is Apple and "until I get their summons to the court I'll continue using it" he then continued "and according to the people I spoke to, this is perfectly legal".

That was almost worth the 2 hours drive through the worst traffic ever...

ipv6 with a Cisco ADSL router a short howto

For a long time I wanted to play with IPv6, but I never liked any of the tunnels I saw. This evening I started wondering if my Cisco 837 ADSL router cannot handle some form of tunnel.

A short time later and:

router#ping ipv6.google.com
Translating "ipv6.google.com"...domain server (195.238.2.21) [OK]

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2001:4860:0:1001::68, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 276/278/284 ms

How to do it: I configured a 6to4 tunnel on the router:

ipv6 unicast-routing
ipv6 cef
! enable ipv6
ipv6 inspect name MyIPv6Inspection tcp
ipv6 inspect name MyIPv6Inspection udp
ipv6 inspect name MyIPv6Inspection ftp
ipv6 inspect name MyIPv6Inspection icmp
! let's have a firewall
interface Tunnel1
no ip address
no ip redirects
ipv6 address 2002:51F0:CCA5::1/128
ipv6 enable
ipv6 traffic-filter ipv6ip in
ipv6 inspect MyIPv6Inspection out
tunnel source Dialer1
tunnel mode ipv6ip 6to4

interface Ethernet0
ipv6 address 2002:51F0:CCA5:DEAD::1/128
ipv6 enable

ipv6 route 2002::/16 Tunnel1
ipv6 route ::/0 2002:C058:6301::

ipv6 access-list ipv6ip
 deny ipv6 any any

Of course the 6to4 ip (the one on Tunnel0) is derived from my ipv4 ip. Which changes now and again. So I uploaded to the flash of my router the following file:

proc doconf { section setting} {
if { [ catch { ios_config $section $setting } errmsg ] } { error "configuration of $section $setting failed"; }
}

set ipaddr [exec "show ip interface Dialer1 | i Internet address"]
regexp {is ([0-9.]*)/} $ipaddr match ip
regexp {([0-9]*).([0-9]*).([0-9]*).([0-9]*)} $ip match a b c d
set newipv6 [format "2002:%2x%2x:%2x%2x::1" $a $b $c $d]
set newintipv6 [format "2002:%2x%2x:%2x%2x:dead::1" $a $b $c $d]
doconf "interface Dialer1" "no ipv6 address"
doconf "interface Dialer1" "ipv6 address $newipv6/128"
doconf "interface Ethernet0" "no ipv6 address"
doconf "interface Ethernet0" "ipv6 address $newintipv6/64"

This is a TCL script that will get the current external ip (from Dialer1) and give the correct IPv6 ips to the right interfaces.

And with alias exec updateipv6 tclsh flash:update-ipv6.tcl I can quickly login and adapt the addresses myself.

The router handles IPv6 autoconfiguration on the inside, so my machine now says:

# ip addr show dev wlan0 scope global
4: wlan0:  mtu 1500 qdisc pfifo_fast qlen 1000
 link/ether 00:19:d2:28:2c:a4 brd ff:ff:ff:ff:ff:ff
 inet 192.168.1.53/24 brd 192.168.1.255 scope global wlan0
 inet6 2002:51f0:cca5:dead:219:d2ff:fe28:2ca4/64 scope global dynamic
    valid_lft 2590061sec preferred_lft 602861sec

The one remaining problem is that when the external ip changes the autoconfig announcements change too, but the old ipv6 IPs remain on the interfaces.

PS: for those not in the know: I work for Cisco but this was done after hours and using public information (of course)

heard at fosdem

The fglrx driver contains 28 million lines of code (!).

That explain the lack of stability...

BTW: planet.grep people at fosdem: want to meet up? Go to Wouter in the Debian room.

hireing myspace inspired designers considered harmful

To see what happens if you hire people who think the average page on myspace looks good to redo your news site you only have to look at the horror of the new site of the vrt.

Even with adblock and noscript tuned I cannot make it into a descent form. A sad day for webdesigners in .be.

Form over function indeed...

Installing debian on a DG33TL G33 system

Someone commented rightfully that I should explain how I got debian installed on the DG33TL.

There are 4 problems:

1. The standard kernel hangs at boot. This is because of a mmconfig related problem. To fix this use "pci=nommconf" as kernel boot option which will ignore the mmconfig information but still enable acpi so you still have a SMP machine.
   
2. The CD/DVD chipset is not yet supported. It is a "Marvell Technology Group Ltd. Unknown device 6101" which not even 2.6.23.9 seems to want to talk to. To solve this I booted from CD, but then continued to install from a USB stick.
3. The standard kernel uses the experimental firewire driver, which gives me an oops. The older firewire driver works perfectly.
   
4. The ethernet card is not recognised. It is a "Ethernet controller: Intel Corporation Unknown device 294c" which works with the 7.6.12-NAPI version e1000 driver.

So to install I used the CD image from Kenshi Muto to install. Afterwards the standard kernel needs the newer e1000 driver. At the moment I'm running 2.6.23.9.

Note to self: direct rendering on G33

If you cannot find out why oh why the Xorg server refuses to play nice and enable direct rendering, remember to check if libgl1-mesa-dri is installed...

So I'm almost there, installing debian on the G33 motherboard (an intel DG33TL) was non-trivial (I'll file a di bug soon), but now the advantages are becoming clear: the video is quite fast, very clear (DVI output) and the Q6600 cpu is just too fast.

Now to restore my backups and I'm back in the game!