Mroddball's Ramblings

Web storage: lighttpd & mod_webdav

mroddball — Sat, 19 Jun 2010 20:37:17 +0000

Today I found wonderful way of sharing files between home and office, and all this without the need of installing anything on my XP box. Just compile lighttpd with mod_webdav and then put few lines in your configuration like so:

auth.backend = "htpasswd"
auth.backend.htpasswd.userfile = "/etc/passwords"
$HTTP["host"] =~ "my.dynamic.ip.domain" {
 auth.require = ( "" =>
     (   "method"  => "basic",
         "realm"   => "webdav share",
         "require" => "user=webdav-user"
     )
    )
    #you don't have to show your files to anyone!
    dir-listing.activate = "disable"

    server.document-root = "webdata/dav/"
    webdav.activate = "enable"
    webdav.is-readonly = "disable"
    webdav.sqlite-db-name = "/var/run/lighttpd/lighttpd.webdav_lock.db"
}

Just to clarify, I had to assign folder to a new domain because for some reason Windows XP won’t use folder provided with URL. I had tried http://my.domain/dav but it still wanted to access http://my.domain/ according to log file. I also created this key in registry, but dunno if it’s necessary.
To mount it in windows just go to My computer, map network drive, use bottom link called ‘Sing up for online….’, next, next, type in your address and that’s it!
The beautiful this is, you don’t need to use port 80 or 443, it works on all of them. Also this is perfect if you’re behind some complex firewall, just run it on some popular port 465, 993, 443, 3389 and it should work.

Exchange 2008 OWA and plain text messages

mroddball — Wed, 14 Apr 2010 17:36:17 +0000

We had quite busy morning today searching for the source of this problem. Every mail going outside our domain was converted to plain text instead of staying in HTML. It turns out that like everything else in world this too could be solved with console, even if it was windows power shell. The value that had to be changed was ContentType. Simply typing: Set-RemoteDomain –Identity:Default -ContentType:MimeHTMLText solved our problem. If you have some other domains in Organisation Configuration -> Hub Transport, then issue command for every one of them. That’s it

BTW: This article was source of solution, even if author was doing quite the opposite

VMware tools on ESX debian guest

mroddball — Tue, 23 Mar 2010 21:05:28 +0000

Recently I realized that VMware tools shipped with ESX don’t always install without a glitch. After creating lenny guest, VMware told me that kernel isn’t compatible with it’s modules, so it will have to compile them from source, great, do it! Quick apt-get install binutils etc. and ./vmware-install. It didn’t go as well as I hoped. Then I thought, hell, these ESX servers are pretty popular, there must be something in contrib repository, it can’t be so hard to do it. It turns out that VMware released ”open source” version of their modules, packages are called open-vm-source and open-vm-tools. First you have to install source, then using m-a tool ‘prepare’, ‘build’ and install it. Don’t worry about gcc, kernel headers etc, ‘prepare’ installs and configures it all for you. Just sit back and after 3 minutes everything will be up and running

Cisco sip phone takes long time to dial ?

mroddball — Sun, 07 Feb 2010 20:37:09 +0000

Last week I’ve been trying to set up my Cisco 7961g with Asterisk. It took me some time to figure out that I need to turn off Nat option to get it working, but nonetheless, it was able to connect. Well, you could think that was it, end of story, but no. After typing number and pressing dial it was waiting about five seconds before it started doing something. Well, if you haven’t done it before, let me tell you. These phones need configuration file, which they take from tftp server. Because they are quite complex and long I didn’t look into them too much, just took it from some site and there you go, it works. Google didn’t give me any answers, so I had to dig into it myself. It’s quite complicated when your phone takes about two minutes to reboot and read new configuration file, so blind guessing was no option. After few, obviously wrong, attempts to fix it, I decided to check out dialTemplate parameter. It points to file holding … well, I don’t remember exactly what, but after defining some examples like “6..” and dialing 678 it started ringing almost immediately. So there you go, if that’s the problem you have, create file and point to it in your SEPmac.cnf.xml.
If you are trying to upgrade your phone, and you encounter problems, try upgrading it to slightly lower version, and then the newest one. If you haven’t tried it, let me give you another advice, always download *.cop files from Cisco, they contain almost everything you need to flash your phone. Good luck!

How to burn CloneCD dual layer images under linux

mroddball — Fri, 11 Dec 2009 22:01:02 +0000

Ever wondered how to do that ? And what the hell to do with this .dvd file ? If you look into it, there is something about LayerBreak, all you have to do is use growisofs with -use-the-force-luke=break: option, so LayerBreak=1234567 in clonecd’s .dvd equals -use-the-force-luke=break:1234567 in growisofs. I personally use
growisofs -speed=2.4 -use-the-force-luke=dao -use-the-force-luke=break:xxxxx -Z /dev/dvd=image.iso
Remeber to put ‘=’ between dvd device and iso image, if you don’t, it will burn iso file, not it’s contents.

Perl equivalent of setuid in C

mroddball — Fri, 04 Dec 2009 19:49:40 +0000

Last week I had to write small server in perl that would replace set of scripts with similar functionality. After some tests it was time to put it on main server, so I wrote init.d script and realised that it would run with root privileges. It couldn’t do any damage, but I couldn’t leave it like that. Well, how hard can it be, was what I thought, after all there was something like setuid in C. After couple of hours on google I came to sad conclusion – there is no such function in perl, so I perused through cpan to find module that would provide me with this feature and there it was - App-Daemon. Great, but then I thoung, wait, how is it able to do this …. Daemon.pm is small, let’s find function that is responsible for this. I couldn’t believe it was so simple, the only thing to do was:
my ($name,$passwd,$uid) = getpwnam($as_user); $> = $uid

If only I had paid more attention while going through Google results I think I would have found it sooner.

Boot linux with PXE and pendrive

mroddball — Thu, 22 Oct 2009 20:32:25 +0000

I’ve been into computers for some time now and although nowadays old hardware is considered of no use, I still keep couple of my previous machines. Oldest one has AMD’s K5 processor which runs at 75 Mhz, 64 MB of memory, and two PCI cards – USB and ethernet. Well, it may be not impressive, but what I really like about it it’s that CPU only needs heat sink (which is really small, not like some Thermaltake copper towers), also I replaced fan in PSU so that there was hardly any noise coming from case. The only problem was hard disk. Racket coming from spinning platters was unbearable and let be honest, almost all hard disk suffer from this problem. They are often the noisiest part of PC. So that got me thinking, how can I still use that old piece of junk and make it quiet. Answer came almost immediately – pendrive. Idea wasn’t bad but there was little problem, there was no way to make it boot from usb. Another idea – buy a CompactFlash card and device to emulate it as hdd, but I didn’t want to waste money, even if it wasn’t much. I was in dead end, there wasn’t a single thing I could think about that would help me.

After several months I came across something called PXE. It let’s you boot computer using ethernet card, dhcp and tftp server. It isn’t as easy as normal hdd or floppy booting, but still it’s fairly straightforward. Almost all network cards support PXE booting, but to be on safe side you better check before proceeding.

DHCP Server

Next thing was to set up dhcp and tftp. First tutorial I found mentioned using ISC dhcp server which I had no experience with. I decided to go in different direction, so after getting some courage (in form of two beers), I dig into dnsmasq documentation, which I was using for a long time. I turned out that not only it was capable of providing PXE booting but also had build in tftp server, lucky! Here are the lines that you have to add to dnsmasq.conf (don’t forget to set dhcp-range too)
dhcp-boot=pxelinux.0 enable-tftp tftp-root=/var/lib/tftpboot

You can put tftp-root wherever you like, I don’t even remember why I decided to put it there. Next thing to do is to get pxelinux.0 ….. to tell you the truth I don’t remember where I found mine, but it turns out that there is one in syslinux-common package in debian, just click on “all” link in table and unpack it with p7zip. After placing pxelinux.0 in tftp it’s time to create some configuration.

cd /var/lib/tftpboot/ mkdir pxelinux.cfg cd pxelinux.cfg

In that directory create default file using your favourite editor, and put this in it:

default huge timeout 1000 label huge kernel bzImg-slack-13 append ro root=/dev/sda1 slowusb rootdelay=15 rootwait

If you ever used lilo you can probably tell that it’s quite similar to lilo.conf. Kernel file defined in fourth line must be placed in tftp root directory. Last line tells kernel where to find root device and what options to use. I had to add rootdelay and rootwait because when it comes to detecting usb devices at boot time it can be quite tricky. On that particular hardware it takes about 5 to 10 seconds to fully detect my pendrive, and if you think that kernel will just politely wait for it, prepare to be surprised.

System

OK, after about 580 words it’s time to prepare that pendrive. There are couple of methods of installing linux on them, but I didn’t really look into any of them, and decided to try one of debian tools called debootstrap. It let’s you install debian in any directory you like in two steps

mkdir /mydebstr debootstrap lenny /mydebstr http://ftp.us.debian.org/debian

It may take some time, but it’s the easiest way I’ve ever seen of installing linux. After it’s done you have to move it to your pendrive, I don’t know if just moving it will work so I always use tar.
mkfs.ext3 /dev/sda1 mkdir /mnt/pxestick mount /dev/sda1 /mnt/pxestick cd /mydebstr tar -cf - . | tar -xf - -C /mnt/pxestick cd / umount /mnt/pxestick rm -r /mnt/pxestick

Kernel

Almost everything is ready, but we still need a kernel, and not just any kernel. The one we need must have build in usb, ext3, usb storage, and preferably networking support and drivers for your card but it isn’t necessary. Unfortunately most distributions provide small kernel with only a few things build in, and leave rest as modules, then at installation they create initrd with necessary modules and everything is OK. One distribution however offers so called huge kernel – slackware. Just visit one of mirrors and get it from slackware-current/kernels/huge.s/ directory. Just put it in tftp root directory and name it accordingly to default configuration file (mine was called bzImg-slack-13).

Final steps

There are two things left, first, debootstrap doesn’t install udev, so you have to do it yourself. I just put it on pendrive in form of .deb file and then used dpkg -i. It isn’t necessary but …. well, quite useful. Second thing – it’s probable that your ethernet card won’t be in slackware kernel, but fear not. In slackware-current/slackware/a/ there is something called kernel-modules. Just unpack it to / on pendrive also download System.map.gz from kernel directory that I mentioned earlier and place it in /boot directory. After booting you can modprobe your card’s module or make it so that’s done automatically. Slackware uses something called XZ to compress files, which was new to me. There are xz-tools in both portage and in debian repositories and if I remember correctly they replace previous lzma tools you might have had on system. Recent version of p7zip may also have support for that format.

It works … ?

Now if you didn’t make any mistakes you should be able to successfully boot PC with that pendrive and dnsmasq. I think I didn’t miss anything vital too, but if you spot something, don’t forget to mention it in form of a comment or something. I may have mentioned that it’s fairly easy to do this, but it turned out to be quite a long post, and you can’t really call something easy when it takes so many words to describe. Well, maybe so, but if you take the essence, it will be only a few copy/paste while some files are downloading, then put it on pendrive and that’s all.

If you think this is cool then there is even more, you don’t even need a pendrive to boot system, there is something called CONFIG_ROOT_NFS. You can get kernel from PXE and use system directly from nfs share on network, and it doesn’t end there, how about booting whole bunch of computers this way ? It has all sorts of benefits, you don’t have to worry about updating software on each of them because everyone uses the same files, and because of that backup is easy too. But that you have to check yourself.

Enjoy!

BTW, I forgot to mention this but AMD K5 needs about 10 W to run, pendrive, usb and network card almost nothing too, so it’s power consumption is about 10 times less than any normal computer (Some AMD Phenoms need 125 W…)

Upload images to imageshack from command line

mroddball — Tue, 13 Oct 2009 18:31:25 +0000

Yet again I had to upload some photos, but having so many of them I thought imageshack would be better and cheaper option than to host them on my site. The only problem was, how to upload that many files without using zip file option, which (afaik) has a limit, or uploading each photo separately. After some time I found python/perl/php scripts that used curl, but those scripts were imo way too long and sometimes overcomplicated. I looked up output of some curl lines and put one of them in bash script.

curl -H Expect: -F fileupload="@$1" -F xml=yes -# "http://www.imageshack.us/index.php"

Output of this command is pure XML, you should really check it out. The script is here pastebin. Easiest way of using it is just to ./up2imgshack picture.jpg, but since I had many files the line for me was

find . -iname "*.jpg" -exec ./up2imgshack {} \;

Enjoy!

Fix java in opera on amd64

mroddball — Fri, 09 Oct 2009 20:05:46 +0000

Haven’t really used java recently, but after some time I forgot what symbolic link I created to get it to work in opera. After some googling I removed old 1.6.0.13 link and created new 1.6.0.15

ln -s /opt/sun-jdk-1.6.0.15/jre/lib/amd64/server/libjvm.so /opt/sun-jdk-1.6.0.15/jre/lib/amd64/

If you happen to have some other version just change paths, enjoy!

Quick way to create gallery with PHP and imagemagick

mroddball — Tue, 29 Sep 2009 20:32:34 +0000

Last week I had to upload some photos for my family, but it’s rather ugly just to have apache’s “Index of” page when people are used to have nice thumbnails. After a couple of minutes I’ve come up with this: pastebin. Just put it in .php file, upload photos in the same folder and type this commands:

mkdir thumb
find . -maxdepth 1 -iname "*.jpg" -exec convert {} -resize 10% -quality 75 thumb/{} \;

Depending on how big your photos are, you will have to play a little with -resize option, but safest way is to define static like -resize 250×188, and if you think some of the pictures won’t look good don’t worry. Imagemagick checks if ratio will be the same after conversion, and in case that it wouldn’t be, height takes precedence. Imagemagick can be used directly from php, but it could take some time to generate all thumbnails and some hosting companies set max_execution_time to lower than minute (default is 30 seconds).

Enjoy!