0xDB central

Tip: BackupPC’s pooling does not work on 3.1.0 (cpool is empty)?

drseergio — Thu, 25 Mar 2010 21:50:36 +0000

If you, like me, are running BackupPC 3.1.0 for one reason or another and have moved your TopDir somewhere else you might have noticed that cpool is not being used rendering the whole pooling feature useless and wasting lots of disk space. If you look into logs you will see entries like:

2010-03-25 22:01:56 BackupPC_link got error -4 when calling MakeFileLink(/var/backup/pc/cabinet/2/attrib, c0bd4dcc462185f61049321f98ce8501, 1)

This is a bug. You can find a 2-line fix at https://bugzilla.redhat.com/show_bug.cgi?id=473944

Tip: BackupPC ignoring per-PC host configuration?

drseergio — Tue, 23 Mar 2010 20:22:53 +0000

Have you followed any guide/HOWTO on installing BackupPC and just cannot figure out why BackupPC seems to ignore your settings and is seemingly using config.pl no matter what?

The root cause of this is that the location of per-PC configuration files differs across versions of BackupPC. If you observe that __TOPDIR__/pc/$host/config.pl is not working then most likely you need to put your config to __CONFIG__/pc/$host.pl (where __CONFIG__ is the location of BackupPC configuration files, e.g. /etc/BackupPC).

I’ve read on a mailing list that the latter is used if FHS (File-system hierarchy standard) is detected and the former if not. Annoyingly, this issue is hard to troubleshoot unless you look into the logs. I have observed that BackupPC was failing on samba even though my host was configured for rsync. This made me realize that probably the config files is ignored completely.

Apart from that BackupPC is really cool, it offers unattended automatic backups. It will pull the data from hosts by connecting through ssh and downloading everything through rsync. In addition to that, it uses pooling – a feature which greatly reduces backup size by storing only unique files. It supports Windows and many flavors of UNIX. For UNIX hosts you can easily configure bare-metal backups (from which you will be able to restore the whole system, not only user data). In addition to rsync, BackupPC uses Samba so it can easily backup Windows machines, too.

Tip: make Apache show cyrillic (non ASCII) characters correctly when serving files

drseergio — Tue, 23 Mar 2010 19:58:06 +0000

I have apache configured to serve my shared files over a local network in addition to NFS, FTP, SMB and whatthehecknot://. I discovered that on a default installation with the UTF8-enabled Gentoo setup the default configuration of Apache is not serving files correctly – all non-ASCII becomes gibberish. Here’s a solution:

Include IndexOptions Charset=UTF-8 in the httpd.conf

Found in here.

My home tech infrastructure getting more interesting

drseergio — Sat, 20 Mar 2010 22:52:11 +0000

Since the moment I’ve moved in to the current apartment I live in I’ve been planning to build a pleasant working place and a simple network/computer infrastructure to store data, watch movies, etc. So far I came up with a following list:

Linksys WRT320N – a 1Gbit 802.11n wireless router. It’s great because it supports dd-wrt GNU/Linux based firmware with which it can do zillions of things – DONE
Acer H340 Atom-based 4xSATA NAS – a great low-power machine which handles storage (software RAID), backup (BackupPC), torrents and any other services I might need. – IN PROGRESS, running Gentoo
Desktop workstation – a powerful machine – PLANING
Dell Zino HD – a great compact machine to be used as a Blu-ray, network player. I like the idea of using a PC instead of a pre-built solution because it is more future-proof. Intending to install Linux on it. – PLANING
and a bunch of misc wireless devices, like laptops.

One of the center items is the NAS from which I intend to provide data to all of the devices around. Here are some shots of Acer H340 during the installation process (installing Gentoo):

I think Acer H340 is a great machine for general storage needs as it can handle 4xSATA drives, has many expansion slots and draws little power. It comes with Windows Home Server and is not designed to be used for anything else. The problem is that there is no video output connector. To install Linux you have few options:

install Linux on a drive, stick it in, boot and hope you can reach it from the network
buy a PCI express X1 compact graphics card (like I did), I got a used one for 48$
buy/make special cable to attach a video connector to the motherboard to use onboard graphics (70$)

When 4 drives is not enough you can always add something like this in the mix: http://www.directron.com/tr8xb.html?gsear=1 http://www.sansdigital.com/towerraid/tr8mb.html. This will allow to add 8 more drives through the use of eSATA and the included expansion card.

There are some resources on the web regarding Linux on H340. Specifically:

My BigMac dissapointment (big Mac, that is!)

drseergio — Sat, 20 Mar 2010 22:01:08 +0000

I completely switched from Windows to Linux 4 years ago. During the years when I used Linux on my main workstation I dreamed of getting a Mac but could not afford one. The reason why I wanted to switch so much is related to numerous X-related issues, like ATI drivers, multi-head support and Intel woes. It all got fixed eventually so by the time of my graduation the desktop was working almost perfectly fine. This did not stop me from dreaming of Macbook Pro as a perfect UNIX desktop which just works.

So… after 6 months of getting used to OSX and Mac I feel great disappointment in the overall performance, specifically responsiveness. I believe my previous machine was slower when I experienced the above-mentioned problems with X but when those got fixed the overall responsiveness and quickness could not be compared. If I take Mac’s hardware specifications then it’s even worst. My Mac has 2.2Ghz dual-core Intel processor, 4Gb of memory. My old machine had 1.8Ghz Intel single-core processor and 2Gb of RAM (it’s a Benq S53 13.3 laptop manufactured in 2007).

To make matters worse I recently got an Atom-based NAS (Acer H340) and it offers a better user experience in terms of speed when I boot-up Ubuntu on it. A colleague of mine says he is observing the same issues. I still think it’s a good machine for work because at the end of the day it just works while with Linux there is a great temptation to try something out which can end-up badly for the productivity.

I am glad that I did not purchase my own Mac machine (I got it from work). If I did I would remove OSX and install Gentoo on it. I don’t like OSX after all. Frankly, I believe it’s better to have a small cheap netbook and a powerful workstation at work/home than an expensive laptop which is so sluggish. Data is in the cloud anyway!

The postman

drseergio — Sat, 20 Mar 2010 21:18:05 +0000

Нашел недавно очередной топ-100 произведений жанра фантастики и был удивлен тем, что прочитал процентов 30 перечисленных там книг – прогресс однако! Благодаря списку пополнил свои запасы литературы на будущее.

Первой из этих книг явилось произведение Девида Брина под названием “Почтальон”. Книга повествует о постапокалиптическом мире пережившим ядерную войну между державами. Главный герой романа – человек, сохранивший понятие чести в эпоху, в которой основное место оставлено выживанию. Гордон, а именно так его и зовут (тут же вспоминаются часы проведенные за игрой в полужизнь aka half-life), в самом начале романа будучи ограбленным к своему великому счастью обнаруживает нетронутый автомобиль почтовой службы былых соединенных штатов америки и использует форму служителя государства. В последствии это втягивает его в приключение, в котором он вживается в роль почтальона и берет на себя роль отвественного за противостояние наступающему каменному веку.

Книга понравилась, рекомендую. Русский перевод доступен на lib.ru, как обычно.

AD snafu

drseergio — Thu, 25 Feb 2010 09:43:19 +0000

I would not rely on these guys when it comes to excellence, that’s for sure!

Profraed everythng

Spotted in Zurich airport.

The future of air travel

drseergio — Tue, 23 Feb 2010 12:13:37 +0000

It happens that I have traveled quite frequently over the last year or so and the only way I could get where I need to is by using airlines. I never had any special problems with it but the amount of inconvenience and troubles I go through now makes love any other way of traveling:

You get searched like a criminal even if you are cooperative
Luggage is regularly lost and searched even if there’s plenty of time between the flights
You have to be at the airport 1-2 hours in advance (depending on the flight)
Ridiculous baggage restrictions
You have to pay for the transport to get to the airport

The only benefit of air travel is that it’s often the only option. I was flying out last Saturday from Zurich to ex-USSR and this is what happened with Macbook Pro – it fell from the security check table because of some wrong and quick movement while I was being searched. I am lucky that the laptop is fully functional as I would not be able to work remotely otherwise!

This is what the future of air travel looks like:

As for me – I prefer trains and cars whenever possible!

IBM DeveloperWorks Linux articles

drseergio — Wed, 17 Feb 2010 19:33:20 +0000

If you find yourself in a need to brush-up your Linux knowledge or would like to learn more about Linux-based system I highly recommend reading series of articles originally written for the IBM DeveloperWorks portal but also available from Gentoo Linux pages. The articles are aimed at people with little or no knowledge of Linux but also offer an advantage of serving as a reference to people who do posses GNU/Linux knowledge:

http://www.gentoo.org/doc/en/articles/

Particularly, the LPI certification 101 is a great guide:

Happy nixing!

Who said nobody wants iPad?

drseergio — Tue, 16 Feb 2010 19:45:53 +0000

I was almost tired to hear numerous comments from all the people around saying how they don’t need an Apple iPad. Few have been giving themselves away already by phrases like, “well, my wife needs a lightwe…”. You get the idea.

Well, I’ve just found this in the news – WIRED iPad app. In other words it’s an application for viewing Wired magazine in digital but there’s more to that – have a look yourself http://www.wired.com/epicenter/2010/02/the-wired-ipad-app-a-video-demonstration/!

I am sure such offerings will make the device attractive to a lot of people even though the initial reception has been cold. Heck, I would buy that too to have such an immersive viewing experience!