Dedicated IP for mail services

hi

would like to know, how do i to assign dedicated ip for email services.

I had multiple ip in server and would like to assign ip as below

a.b.c.d for web/domain/subdomain
e.f.g.h for mail/posfix/roundcube

You can change your mail IP using DNS tool in CWP. Just set up new A record for mail. For roundcube you will have to create subdomain like webmail.yourdomain.com and change apache vshost file.