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To redirect all pages of a old web site to a main page of new web site, we can work with mod_rewrite on apache web server as the following.
RewriteEngine on
RewriteRule ^.*$ http://www.newwebsite.com/ [R=301,L]
Or, we can modify above RewriteRule as the following, users will be redirected to same path on new web site.
RewriteEngine on
RewriteRule ^.*$ http://www.newwebsite.com/$1 [R=301,L]
To create a encrypted key,
# mkdir /etc/key
# dd if=/dev/random of=/etc/key/usbbackup-key bs=1 count=256
# chmod 600 /etc/key/usbbackup-key
To load necessary encryption Linux kernel modules,
# modprobe dm-crypt
# modprobe sha256
# modprobe aes
and add the following lines at /etc/modprobe.d/aliases to load above modules at system startup.
alias sha256 sha256_generic
alias aes aes_generic
Creaation of encrypted file system with cryptsetup
# cryptsetup --verbose --cipher=aes-cbc-essiv:sha256 --key-size=256 luksFormat /dev/sdf1 /etc/key/usbbackup-key
# cryptsetup --key-file=/etc/key/usbbackup-key luksOpen /dev/sdf1 cryptousb
# mke2fs -j -O dir_index,filetype,sparse_super /dev/mapper/cryptousb
An alternative command to make a ext3 filesystem with largefile support.
# mke2fs -j -T largefile -L "usbbackup" /dev/mapper/cryptousb
Add passphrase access to encrypted partition in case partition which holding the key becomes unusable. Otherwise data will be inaccessible.
# cryptsetup --key-file=/etc/key/usbbackup-key luksAddKey /dev/sdf1
DDoS (Distributed Denial of Service) attack is a nightmare of system admins. It makes your internet services or systems are out of service at the end by producing a lot of service requests.
Apache module mod_evasive
mod_evasive is a good Apache module to provide some protection to Apache servers from DDoS attacks. It becomes a package in main section of Debian repos from Lenny.
Installation of mod_evasive on Lenny
To install mod_evasive for Apache 2 on Debian Lenny, simply run aptitude install as following.
# aptitude install libapache2-mod-evasive
During package installation, Apache service will be restarted on your system, and mod_evasive is already enabled.
You may add additional parameters for mod_evasive, edit /etc/apache2/mods-available/mod-evasive.load file, and add the following lines.
<IfModule mod_evasive20.c>
DOSHashTableSize 3097
DOSPageCount 5
DOSSiteCount 100
DOSPageInterval 1
DOSSiteInterval 1
DOSBlockingPeriod 600
</IfModule>
Debian GNU/Linux 5.0 (Lenny) becomes stable version on Valentine Day. We upgraded old stable 4.0 Etch server remotely and successfully.
Summary of upgrading procedures:
Apache web server is a long-time leader in web server market share. According netcraft survey in January 2009, its market share is slightly increasing by 1% last month in current global financial problem.
