ISPConfig 3 - MultiServer Setup moved from one server to another.

Hello!
Listed below is a representation of our new server details:
master.server.com = ISPConfig Panel & DB Server
web.server.com = Web Server & File Server

We have an ISPConfig 3 MultiServer setup and we moved it from one server to another and we need to change the ip address and hostnames. It's working perfectly with the new ip address and old hostnames.
I updated/added the new hostnames to the ff files:
System > Server Config (new hostnames(fqdn) and new ip address)
System > System --> Server Services – edit names of servers
/etc/hosts
/etc/network/interfaces
/etc/resolv.conf
and added this in master.server.com ispconfig database:
GRANT ALL PRIVILEGES ON *.* TO 'root'@'web.server.com' IDENTIFIED BY '(rootpass)' WITH GRANT OPTION;
GRANT ALL PRIVILEGES ON *.* TO 'root'@'new.webserverIP.com' IDENTIFIED BY '(rootpass)' WITH GRANT OPTION;
reboot master.server.com and web.server.com

After changing the hostname and reboot, when I try to connect to master.server.com from web.server.com there is a database connection error.
mysql -h master.server.com -u root -p
ERROR 1045 (28000): Access denied for user 'root'@'web.server.com' (using password: YES)
What's causing this? is there a right process for doing this.

I run the /usr/local/ispconfig/server/server.sh at web.server.com and the result is:
- WARNING - There is already a lockfile set, but no process running with this pid (1733). Continuing.
no problems on the master server

It's my first time to use ispconfig.

-Rose

 

Okay Till, I'll try it later. thanks

And since we have a new ip for all the servers and new hostname... Do I need to change anything from the database ?

-Rose