Category Archives: Linux

VPS.net beta testers wanted for new VPS products

VPS.net (a brand of the UK2 group) is looking for VPS beta testers to receive a free VPS for testing.

There’s only 50 places available so, if you want to take part in the beta, go sign up now! We’re looking for users with some experience of VPS/servers, who can provide useful feedback on their experiences with the service.

See also the description of what a VPS cloud is, and how the design provides scalability and reliability for VPS users.

Debian Xen guests without /dev/pts – no SSH

I’ve been playing with Xen on a Debian host machine. I created a couple of guest machines using xen-create-image (set to use debootstrap to automatically install + configure a basic Debian install on the guest), and was unable to SSH to the guests – I got:


[davidp@masterplan ~]$ ssh 10.1.1.20 -l root
root@10.1.1.20's password:
PTY allocation request failed on channel 0
stdin: is not a tty

I struggled with this for a while, for some reason accessing the guest’s console with xm console didn’t seem to work either.

However, I now managed to get console access to one of them using xm console domain, and found that /dev/pts wasn’t mounted – it wasn’t listed in the fstab file that had been created.

I added the following to /etc/fstab :


none /dev/pts devpts defaults 0 0

Now I can SSH to the guests. :)

Labelling FAT/FAT32 partitions in Linux

Mostly a post for my future refererence, as it took some Googling to find this, but it might be useful to others.

I wanted to view/change the “drive label” for a FAT partition. This is done with the mlabel tool from the mtools package, but it has a strange insistence on setting up “drive letter” mappings, in /etc/mtools.conf or ~/.mtoolsrc, so that you can use it as, for example:


mlabel e:

Um, no thanks. I don’t want to map a Windows-like notion of drive letters to a partition which may appear at a different device each time (it’s a USB device; the point of having the label is to not have to know or care what device node it’s been assigned this time – if USB devices are connected in a different order, it might not be /dev/sdf next time).

The option needed is -i which doesn’t appear to be documented in the mlabel manpage, used along with the fake drive letter ::, for example:


# setting:
[dave@ruthenium ~]$ sudo mlabel -i /dev/sdf1 ::DAVEBLACKBERRY
# viewing:
[dave@ruthenium ~]$ sudo mlabel -s -i /dev/sdf1 ::
Volume label is DAVEBLACKBERRY

With that done, I can then add an entry to /etc/fstab which identifies the device by its label:


[dave@ruthenium ~]$ grep BLACKBERRY /etc/fstab
/dev/disk/by-label/DAVEBLACKBERRY /mnt/blackberry vfat defaults,uid=dave,gid=users 0 0

I should have been able to use LABEL=DAVEBLACKBERRY rather than the long /dev/disk/by-label/... notation, but LABEL= didn’t work, and I didn’t have tiem to figure out why :)

yaourt for Arch Linux

Found yaourt this evening – excellent tool for Arch Linux users, a wrapper around pacman (the standard Arch package manager) which also supports finding packages in the AUR (Arch User Repository) and installing from there.

Excellent tool.

Playing with Ohloh

I’ve been having a quick play with Ohloh, and it seems pretty good. It’s “a website which provides a web services suite and online community platform that aims to map the landscape of open source software development.”

I figured it was worth getting my Perl modules listed, if only to boost the amount of Perl code listed there – I don’t think enough people sing Perl’s praises as they’re busy doing real work with it, so it appears to some to be going “the way of the dinosaurs”.

Ohloh seems impressive so far, with features to hook in to your source control system (Subversion in my case) to see contributors, change history etc. The only drawback is that it does not like re-organisation of the repo, and I re-organised mine to get all the code I’m willing to publically expose under a certain path in the repo, so I can point svnserve at that path, whilst some other code sits at another level. This means that, as far as Ohloh can see, there’s only ever been one commit to my projects. It’s a known problem (according to this forum post).

So far I’ve added SMS::AQL and HTML::Table::FromDatabase – other projects to follow.

xmkmf missing – install imake

I was installing a fairly old piece of software on Arch Linux, and it was failing because I didn’t have xmkmf installed. After some longer Googling than would be expected, I found that xmkmf is part of imake (which was distributed with XFree86, but is no longer used by XOrg).

So, for the benefit of anyone Googling for, say, “xmkmf: command not found” on an Arch Linux system, install the imake package (pacman -S imake) and all will be well.

KDE 4.1 – very nice

KDE 4.1 was released today, and is already in Arch Linux‘s repos, so I decided to update and give it a try.

First impressions – pretty slick indeed, especially after turning on proper compositing support for various funky effects including see-thru windows, “wobbly windows” etc – lots of which is fairly pointless but very nice at the same time :)

So far it seems very polished, it looks like the KDE team have put in a whole lot of work here!

Screenshots/videos may follow, if I get a chance (although I’m sure there’s enough out there already).

Even with the extra eye-candy enabled, the system feels at least as responsive as it did under KDE 3.5, and I think even more responsive actually.

X failures with ATI driver & Xinerama after upgrade

Arse – I updated my Arch Linux install last night, and X will no longer start using my previous config. I can start X using the vesa driver, so X itself isn’t broken, but when I try to start up with my multiple monitor setup (3 screens on 3 seperate ATI Radeon 7000 PCI cards) I get a crash, with the following backtrace:


Backtrace:
0: X(xf86SigHandler+0x7e) [0x80d9d5e]
1: [0xb7ef4420]
2: X(xf86RandR12SetRotations+0x6b) [0x80f58ab]
3: X(xf86CrtcScreenInit+0x9e) [0x80f173e]
4: /usr/lib/xorg/modules/drivers//radeon_drv.so(RADEONScreenInit+0x17fa) [0xb7adfcaa]
5: X(AddScreen+0x1fc) [0x80733dc]
6: X(InitOutput+0x21e) [0x80a769e]
7: X(main+0x296) [0x8073b66]
8: /lib/libc.so.6(__libc_start_main+0xe0) [0xb7cb9390]
9: X(FontFileCompleteXLFD+0x201) [0x80730d1]

How annoying.

I think the issue is down to changes in the X server for Xinerama (used to spread your display across multiple screens) to use RandR, which doesn’t seem to play well.

I’ll post updates here as/when I find a fix.

Using rankmirrors script for faster Arch Linux package downloads

If you use Arch Linux I’d strongly suggest using the snippet of code below to use rankmirrors to sort your pacman repository mirrors into an optimal order, to use the fastest servers first.


cd /etc/pacman.d
for repo in *; do
echo "Processing $repo..."
mv $repo $repo.b4.rankmirrors
rankmirrors -v $repo.b4.rankmirrors > $repo
done

I was getting an average of about 300-400K/sec; after doing this, I was reaching 10M/sec!