Disable PING replies on Linux

You may want to disable ping replies for many reasons, may be for a security reason, or to avoid network congestion.

Disable ping reply Temporarily

# echo "1" >  /proc/sys/net/ipv4/icmp_echo_ignore_all

Also, to enable the ping reply back, set the value to “0″ as shown below.

# echo "0" >  /proc/sys/net/ipv4/icmp_echo_ignore_all

How-To: Recover root password under linux with single user mode

It happens sometime that you can't remember root password. On Linux, recovering root password can be done by booting Linux under a specific mode: single user mode.
This tutorial will show how to boot Linux in single user mode when using GRUB and finally how to change root password.

During normal usage, a Linux OS runs under runlevels between 2 and 5 which corresponds to various multi-user modes. Booting Linux under runlevel 1 will allow one to enter into a specific mode, single user mode. Under such a level, you directly get a root prompt. From there, changing root password is a piece of cake.

Resetting ELASTIX VOIP Server

Log on to your elastix voip server n use your root accaunt
type  :





sqlite3 /var/www/db/acl.db "UPDATE acl_user SET md5_password='`echo -n newpassword|md5sum|cut -d' ' -f1`' WHERE name='admin'" 

Replace newpassword with the password you want to use for the admin login.

or to reset the password to “password” you can use the following command:

sqlite3 /var/www/db/acl.db "UPDATE acl_user SET md5_password='5f4dcc3b5aa765d61d8327deb882cf99' WHERE name='admin'"

done
- FIN -