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Lighttpd / Apache : Run Xcache in Chrooted Jail

Recently I wrote about installing and running Xcache under Red hat enterprise Linux and CentOS Linux. By default Xcache use /dev/zero for caching. All you have to do is create /dev/zero in chrooted jail. Type the following command (assuming that your jail is located at /lighttpd.jail directory):
# mkdir -p /lighttpd.jail/dev
# mknod -m 666 /lighttpd.jail/dev/zero c 1 5

Just restart your web server and xcache should work under chrooted lighttpd web server.

RHEL 5.1 has been released. Redhat announced the availability of Red Hat Enterprise Linux 5.1, with integrated virtualization. This release provides the most compelling platform for customers and software developers ever, with its industry-leading virtualization capabilities complementing Red Hat's newly announced Linux Automation strategy. It offers the industry’s broadest deployment ecosystem, covering standalone systems, virtualized systems, appliances and web-scale "cloud" computing environments.

Besides supporting Linux virtual machines, RHEL 5.1 will also support Windows XP, Windows 2000, Windows Server 2003 and the forthcoming Windows 2008, Crenshaw said. RHEL 5.1 uses Xen for its virtualization.

How do I upgrade to RHEL 5.1?

Login as the root user and simply type the command to fetch all updates via RHN:
# yum update
Depend upon your network condition and software configuration it may take anywhere between 5-20 minutes. Once completed, just reboot the server:
# reboot
Verify that everything is working fine:
# netstat -tulpn
# netstat -nat
# tail -f /var/log/messages
# egrep -i 'error|warn' /var/log/messages
# egrep -i 'error|warn' /path/to/apps/log

Community driven enterprise CentOS Linux users should expect update soon too. You can apply above commends to upgrade your CentOS box.

If you have recently updated your Red Hat Enterprise Linux Server release 5.1 (Tikanga) / CentOS 5.1, dovecot imap server might give out the following error:

Nov 5 13:21:13 p5ora1 dovecot: imap-login: imap-login: error while loading shared libraries: libsepol.so.1: failed to map segment from shared object: Cannot allocate memory
Nov 5 13:21:13 p5ora1 dovecot: pop3-login: pop3-login: error while loading shared libraries: libsepol.so.1: failed to map segment from shared object: Cannot allocate memory

This error is not related to shared libraries. You need to set maximum process size in megabytes. If you don't use login_process_per_connection you might need to grow this. Just open /etc/dovecot.conf file
# vi /etc/dovecot.conf
Find line read as follows:
login_process_size
Uncomment and set it to 64:
login_process_size = 64
Save and close the file. Restart dovecot imap server:
# /etc/init.d/dovecot restart

The Dovecot package on x86_64 (64 bit system) kernels requires the parameter "login_process_size = 64" to be added to /etc/dovecot.conf after an upgrade to RHEL / CentOS 5.1.

If you ever worked for Government or Defense organization, you may come across a request for Department of Defense (DoD) compliant disk wipe program to remove files / disk securely. There are many programs exists for doing the same job. One of my favorite program is scrub, which writes patterns on special files (i.e. raw disk devices) or regular files to make retrieving the data more difficult. Scrub implements user-selectable pattern algorithms that are compliant with DoD 5520.22-M or NNSA NAP-14.x. The dod scrub sequence is compliant with the DoD 5220.22-M procedure for sanitizing removeable and non-removeable rigid disks which requires overwriting all address able locations with a character, its complement, then a random character, and verify.

Download scrub

You can download scrub here. The package is available in both source and binary releases for
=> Redhat Enterprise Linux (RHEL 4 / 5)
=> Debian / Ubuntu Linux
=> HP-UX UNIX
=> Mac OS etc

How do I use scrub?

Scrub operates in one of three modes:

  1. The special file corresponding to an entire disk is scrubbed and all data on it is destroyed. This mode is selected if file is a character or block special file. This is the most effective method.
  2. A regular file is scrubbed and only the data in the file (and optionally its name in the directory entry) is destroyed. The file size is rounded up to fill out the last file system block. This mode is selected if file is a regular file.
  3. file is created, expanded until the file system is full, then scrubbed as in 2). This mode is selected with the -X option.

Examples

Scrub mysensitive.file.txt file, enter:
$ scrub mysensitive.file.txt
Output:

scrub: using NNSA NAP-14.x patterns
scrub: padding mysensitive.file.txt with 3998 bytes to fill last fs block
scrub: scrubbing mysensitive.file.txt 4096 bytes (~4KB)
scrub: random  |................................................|
scrub: random  |................................................|
scrub: 0x0     |................................................|
scrub: verify  |................................................|

To use patterns compliant with DoD 5220.22-M, enter:
$ scrub -p dod mysensitive.file.txt
Output:

scrub: using DoD 5220.22-M patterns
scrub: padding mysensitive.file.txt with 3998 bytes to fill last fs block
scrub: scrubbing mysensitive.file.txt 4096 bytes (~4KB)
scrub: 0x0     |................................................|
scrub: 0xff    |................................................|
scrub: random  |................................................|
scrub: 0x0     |................................................|
scrub: verify  |................................................|

Erase /dev/sda1 - the special file corresponding to an entire disk is scrubbed and all data on it is destroyed, enter:
# scrub /dev/sda1

Related recommended program

Please note that following programs are not compliant with DoD 5220.22-M or certified, but sufficient for home users.
=> wipe, shred and srm utilities.

See also:

Currently Dell only offers Red Hat Enterprise Linux (RHEL) and Suse Novell on Dell Server. Canonical, the company that supports Ubuntu Linux, is trying to work out a deal with hardware vendors such as Dell to make Ubuntu available preinstalled on servers.

Ubuntu Desktop from Dell was the first preinstalled mainstream distro for end users. It's been hard to tell how popular the Ubuntu desktop has been for Dell, which started selling the OS in May on two desktop PCs and the Inspiron E1505n notebook. Asked how well those PCs have sold, Canonical referred the questions to Dell. A Dell spokeswoman said the figures are confidential. I'm quite sure there will be a good demand for server product too.

=> Canonical chases deals to ship Ubuntu Server preinstalled

How to: Upgrade VMWARE Server under Linux

Build 56528 is a release build of VMware Server 1.0.4. It is a maintenance bug fix release to address security issues. Upgrading VMWare server is a piece of cake under Redhat Enterprise Linux / CentOS Linux version 5.0.

Please note that following instructions are tested on RHEL 4.5, 5.0 and CentOS Linux 5.0 only. You can use tar ball based package to upgrade vmware under Debian Linux.

Find out current VMware server version

First find out current vmware server version, enter:
# vmware -v
Output:

VMware Server 1.0.3 build-44356

You can download the latest version from official site.

Shutdown all VMWARE guest oses / vps

Login to each running VM and bring down (halt) guest operating system. You can also use vmware server console or web based interface for the same purpose.
Stop VMWARE Server:
# /etc/init.d/vmware stop
Output:

Stopping VMware services:
   Virtual machine monitor                                 [  OK  ]
   Bridged networking on /dev/vmnet0                       [  OK  ]
   Virtual ethernet                                        [  OK  ]

Stop VMWARE Webbased interface:
# /etc/init.d/httpd.vmware stop
Output:

   Shutting down http.vmware:                              [  OK  ]

Download VMWARE Server

Use wget the ultimate command line downloader
# cd /tmp
# wget http://download3.vmware.com/software/vmserver/VMware-server-1.0.4-56528.i386.rpm
# wget http://download3.vmware.com/software/vmserver/VMware-mui-1.0.4-56528.tar.gz

Upgrade VMWARE server

Use rpm command to upgrade VMWARE server, enter:
# rpm -Uvh VMware-server-1.0.4-56528.i386.rpm
Output:

Preparing...                ########################################### [100%]
   1:VMware-server          ########################################### [100%]

Reconfigure VMWARE Server

Just reconfigure Vmware server with old values/options:
# vmware-config.pl
Just accept accept the End User License Agreement and press CTRL+C. Now configure server with old values:
# vmware-config.pl -d
Output:

aking sure services for VMware Server are stopped.
Stopping VMware services:
   Virtual machine monitor                                 [  OK  ]
   Bridged networking on /dev/vmnet0                       [  OK  ]
   Virtual ethernet                                        [  OK  ]
Configuring fallback GTK+ 2.4 libraries.
In which directory do you want to install the mime type icons?
[/usr/share/icons]
What directory contains your desktop menu entry files? These files have a
.desktop file extension. [/usr/share/applications]
In which directory do you want to install the application's icon?
[/usr/share/pixmaps]
Trying to find a suitable vmmon module for your running kernel.
...........
...
.....
*** Output truncated ***

Upgrade VMware Server Web-based management interface

The VMware Server Web-based management interface. Install on your VMware Server system to enable control from a Web browser. Untar and install the same:
# tar -zxvf VMware-mui-1.0.4-56528.tar.gz
# cd vmware-mui-distrib/
# perl vmware-install.pl

Just follow on screen instructions to install Web-based management interface. Finally just start all guest oses.

Oracle 11g for Linux x86 has been released and available for download from official web site:
Oracle Database 11g extends Oracle's unique ability to deliver the benefits of grid computing with more self-management and automation, making it easier to innovate faster with confidence using Real Application Testing, manage more data for less with advanced partitioning and compression, and much more.

The following are the operating sytem requirements for Oracle Database 11g release 1:
=> Asianux 2.0
=> Asianux 3.0
=> Oracle Enterprise Linux 4.0
=> Oracle Enterprise Linux 5.0
=> Red Hat Enterprise Linux 4.0
=> Red Hat Enterprise Linux 5.0
=> SUSE Enterprise Linux 10.0

I'm sure you will be able to use Debian or Cent OS for testing purpose.

Download Oracle Database for Linux

=> Click here to download Oracle 11g for Linux

See also:

=> How to: Install Oracle Database XE Server on my Ubuntu / Debian Linux desktop system