Linux: Desktop Linux Survey Results Published

Posted on in Categories News last updated November 30, 2005

In Q3/2005 OSDL Desktop Linux (DTL) Working Group launched a month-long online Linux Client survey with a goal of reaching consensus on barriers to desktop adoption and priorities. It has published Desktop Linux Survey Results. It is base upon 3,300 user responses. Top two reasons given for deploying Linux on the desktop:

  • Employees requesting Linux (user demand) and
  • Competitors have successfully deployed Linux

So Microsoft claim of TCO (total cost of ownership), or security are just useless :D. You can read complete survey here (in PDF file) or just go to Slashdot discussion. Firefox 1.5 final now available, just friendly remainder to all of you 😉

Temporary memory files and shell scripts

Posted on in Categories News last updated November 28, 2005

Recently we got lots of discussion about shell scripts that create a temporary memory files and only available to the invoked shell but not visible to any other user or process except root user. If we use /tmp directory to create file then it will be available to everyone. Next comes the idea of here document feature. For example following simple shell program uses here document feature

#!/bin/bash
cat << STOP
DATA1=””
DATA2=””
echo $DATA1
STOP

However soon we discovered that here documents is implemented as temporary file by bash shell. For example if we run strace on script we can easily see it is opening file in /tmp
$ strace -f script.bash

Bottom line if data is such critical scripts are useless, it is better go with private directory or write program in C.

How do I Read ext2 or ext3 filesystems under Windows 2000 or XP Desktop?

Posted on in Categories File system, Linux, Windows, Windows server last updated November 24, 2005

Asked by Payal K.

Q. I would like to know – can I access Linux ext3 partitions from windows 2000 server (dual boot) or windows XP desktop, as I have tons of MP3 and video files downloaded under Linux.

A. It is true that you can easily access your Windows partitions from Linux. However with small free utility called Explore2fs you can easily access Linux ext3 or ext2 partitions too without any problem.

Does ext3 work with windows?

Short answer – Yes.

You can always get your favorite MP3/video or PDF file stored inside Linux ext3 file system. This utility works on

  • Windows 95
  • Windows 98
  • Windows ME
  • Windows NT 4.0
  • Windows 2000
  • Windows XP
  • Windows Server 2003

However please note that I don’t recommend to install this utility on a production Linux serer (if you have one) as it does not enforce security permission from windows operating system.One more thing before using this utility make sure you have a backup of all important data.

Download Explore2fs

=> You can download Explore2fs, the WIN32 explorer for Linux ext2fs partitions here.

Read and Write access to Linux file system from Windows

As pointed out by Anonymous user you can use Ext2 Installable File System For Windows, which provide Complete reading and writing access to files and directories of volumes with the Ext2 or Ext3 file system. You can download the software here.

The Sun Java Desktop System is available free for OpenSolaris

Posted on in Categories News last updated November 22, 2005

The Java Desktop System is not a secure but very good total enterprise desktop software system. It is the best alternative to Microsoft Windows XP and now sun made it Free and available on OpenSolaris.However this the source-only release contains the major new features such as GNOME 2.10, Firefox 1.5b,and Thunderbird 1.5b. It means you need to compile or build desktop for yourself. Open Solaris has howto document that explains how to build JDS on OpenSolaris. More information can be found at OpenSolaris Desktop community site.

Between if you use and love Solaris 10 OS, then tell your story to Sun to win an Apple iPod. In addition to this, there is free Solaris Technology Training Event (Atlanta, Georgia, U.S.) On December 7, 2005, attend “How-to” training on an array of hot technology topics, including developer tools, OpenSolaris, security, performance, and more. You can win cool prices here too.

Dual network interface card to optimize Linux server backup process

Posted on in Categories News last updated November 22, 2005

The majority of the time small and medium size business use the single dedicated Linux/*BSD box for hosing web site, database server, mail server. These servers are so busy round the clock (yes we do have lots of such client, they have dual XEON/AMD or P4 with 4-8 GIG RAM). Since backup is such critical procedure, we have an automated snapshot (hourly, nightly, and full monthly backup facility) procedure for all dedicated UNIX/ Linux/Windows boxes.

Snapshot Backups provide a convenient, automatic way to save copies of data/website/ftp/mysql data/site/files without using valuable disk space. Backup software (or Linux scripts) stores a copy, or takes a “snapshot,” of customers dedicated box every 2 hours, nightly, weekly etc. These snapshots are saved and dated for customer by our software and can be restore directly from clients control panel, in the event that any of files are accidentally deleted or changed.

Although this facility is ultra cool, it has its own disadvantage too on clients’ dedicated Linux box. On any busy server things started to get worst because of hourly hot snapshot backup. Our customer started to report us that while backup is in progress ftp/www site becomes slow. We quickly realize that single NIC is the problem, so we have upgraded all old servers to dual NICs. Therefore, backup data is piped through a second NIC, isolating the process from frontend traffic.

Linux  eth0  --> Public interface for ftp/http/mysql traffic
Box    eth1  --> Private interface for backup

eth1 IP(s) only accessible in our data center, all outside access to eth1 IP is blocked at enterprise IDC firewall. This is done for security reason.

We have products from NetApp for central storage and snapshot facility (in case if you are wondering what we are using for central storage). You can find information about NetApp here.

Result was neat and now no more complaints from customer. We use same solution for shared hosting customer too. However if your IDC is small then you can use any (netapp products are expensive) other Linux/UNIX box and couple of ftp script could do the same backup trick and make sure you use second NIC to pump backup data. Here is sample diagram that will help you to grasp the concept

  1. All eth0 connects to Internet
  2. All eth1 connects to Private switch inside IDC
  3. Linux based backup server should not be accessible outside your network
  4. You need to create perl/shell script to automate backup procedure

How do I run 32bit application under itanium (ia64) system running RedHat Linux?

Posted on in Categories News last updated November 21, 2005

Well some time you do not have access to source code or you really do not want to compile the code. Then Red Hat Enterprise Linux provides the service called ia32el. The ia32el package contains IA-32 Execution Layer platform which allows emulation of IA-32 binaries on IA-64.(i.e. it allows to run 32-bit applications through the use of Intel’s IA-32 Execution Layer). The IA-32 Execution Layer and 32-bit compatibility packages together provide a runtime environment for 32-bit applications on the 64-bit native RedHat Linux distribution.

Use rpm command to verify that it is installed:
# rpm -qa | grep ia32el

If service is, installed then check the status of service:
# service ia32el status

If it is not installed then install it via up2date command or install it from other extra CD provided by Red Hat Linux. Once installed you can start service with command:
# service ia32el start

And make sure you have /emul dir. If this failes then you need to recompile the package from source, code again on 64-bit computer. Also make sure you update ia32el package, it has some bugs that can cause problem.

Between we have added Linux & UNIX Top Sites project to our community site. It is a top sites directory that aims to show you the best Linux/UNIX related site or blogs. We have different categories to suit your needs. Ranking of pages is done according to number of unique visit each site receives every week. If you have a site or blog related to Linux/UNIX and wish to have your site listed, please register your site free.

See Red Hat Linux documentation for more information.

HP-UX: Understanding device file naming convention

Posted on in Categories News last updated November 19, 2005

Both HP-UX and Sun Solars uses almost same device file naming convention. Typically it look like as follows:

c#t#d#

Let us try to understand what those letters

  • c – Instance number of interface card
  • t – SCSI target address
  • d – Device number aka SCSI LUN

Use ioscan command to get information about your device under HP-UX. A block device file is always in /dev/dsk and a character device file in /dev/rdsk directory.

  • /dev/dsk/c0t5d0 – Block device file
  • /dev/rdsk/c0t5d0 – Raw device file

I just wish both of them were use device file naming convention like linux (/dev/sda1).

HP-UX – logname command is not working

Posted on in Categories News last updated November 18, 2005

Asked by M. Sukumar

Q. When I logged into my server, I got these error
logname: could not get login name

I am not getting what is the problem for not executing these logname command in /etc/profile, and also I checked my /etc/utmp /etc/utpmx files are not corrupted. Skumar further tell us that he login over ssh, and he has tried the full path /usr/bin/logname, and permission are also good, but it is not working. Remaining commands like who , who am i , all are working properly. Further command ‘echo $LOGNAME’ giving him correct output.

A. Since files are /etc/utmp /etc/utpmx files are not corrupted, problem is basically related to sshd server. By setting UsePrivilegeSeparation from:

UsePrivilegeSeparation Yes

To

UsePrivilegeSeparation No

should fix the problem. Change the values in sshd_config file and restart the network. Please note that UsePrivilegeSeparation – specifies whether sshd separates privileges by creating an unprivileged child process to deal with incoming network traffic. After successful authentication, another process will be created that has the privilege of the authenticated user. The goal of privilege separation is to prevent privilege escalation by containing any corruption within the unprivileged processes. The default is “yes”. Privilege Separation should be always turned on for security. You should upgrade both sshd and HP-UX with up to date patches to solve this problem.