Script to rotate IP of a cpanel domain

 

 

SITUATION: One of my customers wants to change ip address of his cpanel account every 10mins. The TTL of the domain was reduced and the following script was created for this purpose. The script uses sqlite database for holding details.

 

 

SOLUTION

 

1) Create a sqlite database to hold the ipaddress and set active flag for only one ip as described below.

 

In this example I have used ip address range 192.142.12.12 to 192.142.12.18 and have set the ip 192.142.12.12 as the active one,

 


# /usr/bin/sqlite3 /root/sqlitetesting/iprounding
SQLite version 3.3.6
Enter ".help" for instructions
sqlite> create table iproundrobin(num INTEGER PRIMARY KEY AUTOINCREMENT, ipv4address VARCHAR(16) NOT NULL UNIQUE,activeflag BOOLEAN);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.12',1);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.13',0);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.14',0);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.15',0);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.16',0);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.17',0);
sqlite> insert into iproundrobin(ipv4address,activeflag) values('192.142.12.18',0);
sqlite> select * from iproundrobin;
1|192.142.12.12|1
2|192.142.12.13|0
3|192.142.12.14|0
4|192.142.12.15|0
5|192.142.12.16|0
6|192.142.12.17|0
7|192.142.12.18|0
sqlite> .exit
#


 

2) Schedule the following script using cron to run at a definite interval,

 

#!/bin/bash

CHANGEIP=/usr/local/cpanel/bin/setsiteip
USERNAME=username

#get the currently active ip and its position
curIP=$(/usr/bin/sqlite3 /root/sqlitetesting/iprounding "select ipv4address from iproundrobin where activeflag=1")
curPos=$(/usr/bin/sqlite3 /root/sqlitetesting/iprounding "select num from iproundrobin where activeflag=1")

#Calculate the next position
nextPos=$(/usr/bin/sqlite3 /root/sqlitetesting/iprounding "select num from iproundrobin where num > `echo -n ${curPos}` ORDER BY num limit 1")

if [ "$nextPos" != "" ];then
  # get the ip of nextPos and set it as the new ip
  newIP=$(/usr/bin/sqlite3 /root/sqlitetesting/iprounding "select ipv4address from iproundrobin where num=`echo -n ${nextPos}`")
else
  # get the ip of first pos and set it as active
  newIP=$(/usr/bin/sqlite3 /root/sqlitetesting/iprounding "select ipv4address from iproundrobin where num=(select min(num) from iproundrobin)")
fi

# set activeflag to 0 of current ip and also set activeflag to 1 of newly selected ip
# At a time value of activeFlag will be 1 for only one ipaddress
/usr/bin/sqlite3 /root/sqlitetesting/iprounding "update iproundrobin set activeflag=0 where ipv4address=\"`echo -n ${curIP}`\""
/usr/bin/sqlite3 /root/sqlitetesting/iprounding "update iproundrobin set activeflag=1 where ipv4address=\"`echo -n ${newIP}`\""

#Set site ip
$CHANGEIP -u ${USERNAME} ${newIP} 2>&1 >/dev/null

#Display the contents of table
/usr/bin/sqlite3 /root/sqlitetesting/iprounding "select * from iproundrobin;"

 

OUTPUT ( Sample run )

# ./script.sh 
1|192.142.12.12|0
2|192.142.12.13|1
3|192.142.12.14|0
4|192.142.12.15|0
5|192.142.12.16|0
6|192.142.12.17|0
7|192.142.12.18|0
# ./script.sh 
1|192.142.12.12|0
2|192.142.12.13|0
3|192.142.12.14|1
4|192.142.12.15|0
5|192.142.12.16|0
6|192.142.12.17|0
7|192.142.12.18|0
# ./script.sh 
1|192.142.12.12|0
2|192.142.12.13|0
3|192.142.12.14|0
4|192.142.12.15|1
5|192.142.12.16|0
6|192.142.12.17|0
7|192.142.12.18|0
# ./script.sh 
1|192.142.12.12|0
2|192.142.12.13|0
3|192.142.12.14|0
4|192.142.12.15|0
5|192.142.12.16|1
6|192.142.12.17|0
7|192.142.12.18|0
# ./script.sh 
1|192.142.12.12|0
2|192.142.12.13|0
3|192.142.12.14|0
4|192.142.12.15|0
5|192.142.12.16|0
6|192.142.12.17|1
7|192.142.12.18|0
# ./script.sh 
1|192.142.12.12|0
2|192.142.12.13|0
3|192.142.12.14|0
4|192.142.12.15|0
5|192.142.12.16|0
6|192.142.12.17|0
7|192.142.12.18|1
# ./script.sh 
1|192.142.12.12|1
2|192.142.12.13|0
3|192.142.12.14|0
4|192.142.12.15|0
5|192.142.12.16|0
6|192.142.12.17|0
7|192.142.12.18|0
#