Dynamic IP address-Based WWW server in Linux

Article Title: implement a dynamic IP address-Based WWW server in Linux. Linux is a technology channel of the IT lab in China. Includes basic categories such as desktop applications, Linux system management, kernel research, embedded systems, and open source.
The Dynamic IP-based server can also open the www Service to accept client access, which can be achieved through the following script. Please first establish a PPP connection, configure Httpd, and test whether it can work.
Create the following script program:
* Web_up: the script used to upload a webpage.
* Web_down: indicates the script for disconnecting.
* Update_uppage: the Perl script creates an HTML page containing the updated IP address.
* Up. HTML_source; Fixed page.
* Down. HTML: Page used for disconnection.
*/Etc/add,/etc/last_add: The file that stores the IP address.
* Ip-down and ip-up: files uploaded when the PPP connection is disconnected and the connection is rejected.
　　
Scripts web_up:
#! /Bin/sh
# Check new ip
New_ip ()
{
If [-f/etc/add]; then
If [-f/etc/last-add]; then
If/usr/bin/diff/etc/add/etc/last_add>/dev/null; then
Exit 1
Else
Return 0
Fi
Else
Return 0
Fi
Else
Exit 1
Fi
}
# Check whether maroon is connected
Try_connect ()
{
If ping-c4-13 128.101.118.21 2> & | grep "0 packets">/dev/null
Then
Return 1
Else
Return 0
Fi
Fi
}
If try_connect
Then
Touch/var/run/maroon_connected
Else
Rm-f/var/run/maroon_connected
Fi
# FTP to update page
If [-f/var/run/maroon_connected] & new_ip
Then
# Update_uppage is perl scripts, exit status is opposite of shell
If (! /Home/honglu/public_HTML/update_uppage)
Then
Cd/home/honglu/public_HTML
If echo "put up. HTML/nlhome/m508/luxxx012/dynamic. HTML" |/usr/bin/FTP maroon
Then
Rm-f/etc/last_add
Cp/etc/add/etc/last_add
Exit 0
Else
Exit 1
Fi
Fi
Else
Exit 1
Fi
　　
Scripts web_down
# FTP to send down. HTML page
If [-f/var/run/maroon_connected]
Then
Cd/home/honglu/public_HTML
If echo "put down. HTML/nlhome/m508/luxxx012/dynamic. HTML" |/usr/bin/FTP maroon
Then
Rm-f/etc/last_add
Else
Exit 1
Fi
Else
Exit 1
Fi
　　
Run the following script:
　　
#! /Bin/sh
If web_down
Then
Shutdown-h now
Else
Echo "can not web_down"
Exit 1
Fi