change hostname in multiple servers environment

[tiger2000]

Dear All,

one of customers deploys zimbra(5.0.9) in 2-server environment, like :
ms1.example.com
ms2.example.com

and they're planning to change them to :
webmail.example.com
ms2.example.com

so that they can apply the commercial certificate for : webmail.example.com and set tls mode to "redirect".

i've read the wiki article here: ZmSetServerName - Zimbra :: Wiki , and i found in step#8

8. Reboot
(Those in multi-server setups: Be sure to change any corresponding references to the old hostname & restart services on all hosts)

could someone address this statement more clearly which corresponding files need to be changed in my ms2.example.com ??

Thanks.