useful stuff

On Debian lenny openssh 5.1 is shipped. These new version allows some nice security configurations.

add to /etc/ssh/sshd_config:

Match User jonas
AllowTcpForwarding no
X11Forwarding no
ChrootDirectory /home
ForceCommand internal-sftp

This will chroot the user jonas to /home. The user jonas could only use sftp, no interactive shell is permitted. Also the user could not run ssh foo@bar 'cat /proc/cpu'.

Warning: The ChrootDirectory have to be root owned!

For all WinSCP users:
-> disable SCP-Callback

For all Linux sftp users:
-> sftp -s /usr/lib/openssh/sftp-server foo@bar.com

New ( version: 9.4.1.1) 3Ware CLI programm is now packaged. You can find it on: jonas.genannt.name.

Please have a look at: Using the tw_cli

If you plan an maintenance shutdown for your website, you can use the mod-rewrite for the maintenance forward.

ReWriteEngine On
ReWriteCond %{REMOTE_ADDR} !^123\.123\.123\.([0-9]+)$
ReWriteRule ^(.*)$ http://your-site.com/maintenance.html [L]

This code will forward all users except from IP block 123.123.123.0/24 to an maintenance site.

If you have got 123.123.123.0/24 you can use the site as normal, and all other users will be forwarded.

The tw_cli from 3Ware for all the 3WARE Controllers is a little bit tricky.

Here are some examples how to use tw_cli:

tw_cli
//irena>info
Ctl Model Ports Drives Units NotOpt RRate VRate BBU
------------------------------------------------------------------------
c0 8506-4LP 4 3 1 0 3 - -

The info command is usefull for checking how many controller are available.

//irena>/c0 show
Unit UnitType Status %RCmpl %V/I/M Stripe Size(GB) Cache AVrfy
------------------------------------------------------------------------------
u0 RAID-5 OK - - 64K 298.099 ON -

Port Status Unit Size Blocks Serial
---------------------------------------------------------------
p0 OK u0 149.05 GB 312581808 0696J1FX608399
p1 OK u0 149.05 GB 312581808 0696J1FX611330
p2 NOT-PRESENT - - - -
p3 OK u0 149.05 GB 312581808 0696J1FX611304

The /c0 show command display which raid units and disks avilable on controller 0.
For the second controller in the system please type /c1 show.

//irena>/c0/u0 start verify
Sending start verify message to /c0/u0 ... Done.

The /c0/u0 start verify command starts an Raid verify on Controller 0 Unit 0.

//irena>/c0/u0 start rebuild disk=1
Sending rebuild start request to /c0/u0 on 1 disk(s)

The command /c0/u0 start rebuild disk=1 starts the rebuild on controller 0, unit 0 and disk 1 (on port 1).


If you are using debian, you can use my debian packages, please see here!

In the past I had some trouble to manage my RSS feeds.

I used Thunderbird for reading my email than the RSS feeds begun to grow up and I used Thunderbird to read my feeds, but it is the wrong program for it. To slow and to big, eats memory.

Today I started my search for an news reader! - I found Liferea.

A small and fast - written in GTK - newsreader. Now I'm happy with the feeds.

Git the (new) revision control systen used by the Linux kernel is very nice, if you know how to use it.

Here are some hints for you/me:

Downloads the git archive to your local directory linux-2.6.16.x:
git clone git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-2.6.16.y.git linux-2.6.16.x

Updates your git archive with the servers archive:
git pull git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-2.6.16.y.git

Lists the available Tags in the Branch:
ls -la .git/refs/tags/

Creates an diff between to Tags:
git diff v2.6.16.24..v2.6.16.25

I really love rdiff-backup

I use rdiff-backup with cron to backup my home directory from my raid 5 to a single harddrive daily.

Today I have done something wrong in Thunderbird, so I deleted my complete INBOX!

No problem.... Mount the backup drive, used rdiff-backup -r now to restore all data.

Result: Lost some Spam mails

Relating to that Virus Scanning entry I think Debian Volatile is better for an up-to-date ClamAV than Backports.org.

Debian Volatile is made for packages that change very often, and you need the current upstream package on a server. Like an up-to-date virus scanning engine.

So simple and this line to your sources.list and run after that an apt-get update.

deb http://ftp2.de.debian.org/debian-volatile sarge/volatile main

BTW: Volatile Mirror List

Now you can install your clamav normally with an apt-get install clamav.

If you want to tunnel VNC session via SSH you shoud start the vncserver on the remote host and than use that command

ssh -C -L 5901:192.168.0.1:5901 hggh.no-ip.org

to create the tunnel!

Than use vncviewer on the localhost with this command:

vncviewer localhost:1

Than you have tunneled VNC throw SSH

I know VNC is not very fast, but it is easy to set up than you need it NOW!