linux

After update from virtualbox 3.x to 4.x the scroll wheel of my mouse stopped working - just behaved as a three button mouse.

Newer versions of debian no longer have an xorg.conf file - since it's not normally needed.

After some searching I found that it has a config loading directory /usr/share/X11/xorg.conf.d/ and virtualbox had added a 50-vboxmouse.conf there.

I changed this file from

Section "InputClass"
        Identifier      "vboxmouse"
        MatchDevicePath "/dev/vboxguest"
        Driver          "vboxmouse"
EndSection

to

The Pro series of NAS from ReadyNAS (Netgear) support iSCSI out of the box. But the NV+ 4disk unit does not. However - a third party plugin is available. Let's look at what is needed to get iSCSI connections between the ReadyNAS NV+ and an iMac running Snow Leopard.

My glassfish process kept dying with "Too many open files" in the log.

I'm not surprised that it has too many - it has quite a few large applications running - but how to increase this?

ulimit -n shows that the user has a default of 1024.

But ulimit -n 2048 gives -su: ulimit: open files: cannot modify limit: Operation not permitted

Some digging leads to /etc/security/limits.conf

Here we added:

As part of Building a debian firewall on a CF card I was trying to make sure that disk writes to the firewall CF card were kept to a minimum.

However - I've never really been able to test this. So I was pleased to find http://samwel.tk/laptop_mode/faq - under section 5 there is a question titled "My disk spins up all the time and I have no clue what causes this. Can I debug this?".

A good source of entropy is needed for random number generation. This affects services that go via SSL amongst other things.

However - in 2.6.x kernels the entropy sources of a system were reduced - as far as I can see it now is only affected by keyboard, mouse and some IRQ interrupts.

I currently have an OpenBSD firewall running on an ancient 586. I have a mini-itx board, CF/IDE converter and a CF card and have been intending to upgrade.

However - rather than OpenBSD I'm going to try for debian (since I know that much better).

This post will end up being a "how I did it" - but at the minute is just a collection of the notes I'm grabbing for now.

For the initial install - I hung a CD-ROM as the slave IDE unit on the primary IDE channel.

I used the 4.0r3 etch netinst CD downloaded from debian.org.

mplayer works best with the real time clock (rtc) device /dev/rtc. It also wants to be able to set frequency up to 1024 as a user.

First make sure the rtc module is loaded - one way is to add rtc to /etc/modules

Now - lots of places I see the recommendation to add

echo 1024 > /proc/sys/dev/rtc/max-user-freq

to your startup scripts. I've never been sure where to hack this in - and the people who are giving the advice have many different suggestions. The whole thing feels like a bad hack.

So - after some investigation - I feel that it is much better to use sysctl - by adding the following to /etc/sysctl.conf

Note to self - here's the tar command you keep having to lookup

cd /path/to/source
tar lcvf - .|(cd /path/to/dest; tar xpvf - )

Just a note to self - to generate a new certificate

openssl req -new -key /etc/ssl/private/keyfile -x509 -days nnn -out /etc/apache2/ssl/certfile

The dnslookup section of the exim4 config contains

# ignore private rfc1918 and APIPA addresses
ignore_target_hosts = 0.0.0.0 : 127.0.0.0/8 : 192.168.0.0/16 :\
172.16.0.0/12 : 10.0.0.0/8 : 169.254.0.0/16

To allow one specific subnet thru change it:
# ignore private rfc1918 and APIPA addresses
ignore_target_hosts = !192.168.3.0/24 : 0.0.0.0 : 127.0.0.0/8 : 192.168.0.0/16 :\
172.16.0.0/12 : 10.0.0.0/8 : 169.254.0.0/16

Here it allows the 192.168.3.x network.

Running xfce4 - and have no gnome control panel - but I needed to change the default browser.

gconftool -g /desktop/gnome/url-handlers/http
gconftool -g /desktop/gnome/url-handlers/https

will tell you what is set - in my case "epiphany %s"

I tend to use opera - so

gconftool -s /desktop/gnome/url-handlers/http -t string 'opera -newpage %s'
gconftool -s /desktop/gnome/url-handlers/https -t string 'opera -newpage %s'

did the trick

This machine is a debian sarge install (2.6 kernel). During installation - it was set up with root as ext3, some swap - and the rest of the disk as an lvm area. All partitions within this area are xfs. All the work was done by the debian installer. Now - we have a new disk which I needed to add.

So - since this is an already running box - the debian installer can't really be used - let's use the actual utilities.

All of the required steps are documented on the LVM HOWTO

First - we need to decide if we are going to use the whole disk or a partition. In this case - the whole disk /dev/hdb. To be able to do this - any existing partition table must be removed

From this blog information on getting mplayer to play .3gp files:

In /etc/mplayer/codecs - find the section for the videocodec ffh263 (just search for it) and add:

format 0x33363273

When using xdm instead of gdm/kdm it's useful to have buttons to allow for shutdown/restart. This is possible using Tcl/Tk and some config tweaks.

Most of the info needed is here:

XDM shutdown buttons

Running a dial-up over bluetooth to a S700i.

Most of this is cargo-culted from the pages listed on http://www.holtmann.org/linux/kernel/ (page no longer available) - with most of it coming from here.

Installed bluez-hcidump, bluez-pin and bluez-utils.

Used hcidump and sdptool to scan for the device - got the device's id.

bluez-pin worked for me - so I kept that.

Config files.

/etc/bluetooth/hcid.conf - unchanged

/etc/bluetooth/rfcomm.conf

rfcomm0 {
bind yes;
device device_id;
channel 1;

At least 2GHz CPU
Between 256 and 512 MB ram
Disk - two 200Gb disks? Maybe LVM? Either XFS or JFS?
2x Hauppauge 350 capture cards or 1 350 and 1 DVB card (is DVB available in Norway)?
Soundcard - probably the on-board one will be good enough
Vid card - TV out - use the 350?

Testing some of the software that Myth TV uses. XML TV for Norway is currently broken in the release version - but the CVS version of the grabber seems to be sorted.

So - how to make a box that is powerful enough but quiet enough? Some of the mini-itx boards look good - but - not enough slots - so ... how to decide what the hardware should actually be?

Looking at setting up a MythTV box (MythTV)

Normal questions - what hardware to get - why can't you get motherboards without inbuilt sound/screen/net etc etc.

Could be fun - so far it may look like

2.x+ GHz processor
2 or 3 250 Gb disks (maybe time to learn lvm?)
Hauppauge 350 encoder/decoder card (1 or 2)

Not sure about graphics card or sound card just yet.

Longer term - add a DVD burner :-)